## Convert Very Large Decimal Integers to Base 62 And Back

The other day I was trying to devise a way of converting arbitrarily large base 10 integers to the order of a billion billion to base 62 and did not get much help from the web. So I devised my own solution using the BC Math extension which ships with PHP by default. So, this solution works upto PHP_INT_MAX which is 9223372036854775807 for 64-bit platform. It also works upto 99 trillion on 32-bit-platform. I used an array as a stack to store successive remainders of division by the base, which is 62, and at the end popped them one by one from the stack to generate the converted base 62 number. The converse, multiplication by successive powers of 62 and addition of those powers helped to convert base 62 back to base 10.

First I used PHP OOPS to create a class called MyBase62Converter. The code is given below:

```class MyBase62Converter
{
private \$base62StrVar = '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz';
private \$baseInt = 62;

function encode(\$decNum)
{
\$base = \$this->baseInt;

\$myStack = array();

\$remainder = 0;

\$base62Str = \$this->base62StrVar;

do
{

\$remainder = bcmod(\$decNum, \$base);

array_push(\$myStack, \$remainder);

\$decNum = bcdiv(bcsub(\$decNum, \$remainder), \$base);

}
while(\$decNum > 0);

\$binNum = '';

while(count(\$myStack) > 0)
{

\$binNum.= substr(\$base62Str, array_pop(\$myStack), 1);
}

}

function decode(\$baseNum)
{

\$base62Str = \$this->base62StrVar;

\$base = \$this->baseInt;

\$hashLen = strlen(\$baseNum);

\$decNum = '';

for(\$i = 0; \$i < \$hashLen; \$i++)
{
\$decNum = bcadd(\$decNum, bcmul(bcpow(\$base, \$i), strpos(\$base62Str , substr(\$baseNum, \$hashLen - \$i - 1, 1))));
}

return \$decNum;
}

}

```

Using the two simple encode and decode functions we can convert base 10 integers to base 62 representation and vice versa.

You can see the example below:

```require_once("lib/class.MyBase62Converter.php");

\$encoder = new MyBase62Converter();

echo "<br />";

echo PHP_INT_MAX." encoded is ".\$encoded = \$encoder->encode(PHP_INT_MAX);

echo "<br />";

echo \$encoded." decoded is ".\$decoded = \$encoder->decode(\$encoded);

echo "<br />";

\$largeNum = bcpow(62, 6) - 1;

echo \$largeNum." encoded is ".\$encoded = \$encoder->encode(\$largeNum);

echo "<br />";

echo \$encoded." decoded is ".\$decoded = \$encoder->decode(\$encoded);

echo "<br />";

\$veryLargeNum = bcpow(62, 7) - 1; //getting 0 due to num expressed in scientfic exponential notation 2.183401055849E+14

echo \$veryLargeNum." encoded is ".\$encoded = \$encoder->encode(\$veryLargeNum);

echo "<br />";

echo \$encoded." decoded is ".\$decoded = \$encoder->decode(\$encoded);

echo "<br  />";

\$max_num = 99999999999999;

echo \$max_num." encoded is ".\$encoded = \$encoder->encode(\$max_num , 62); //99999999999999

echo "<br />";

echo \$encoded." decoded is ".\$decoded = \$encoder->decode(\$encoded);

echo "<br />";

\$new_num = 63;

echo \$new_num." encoded is ".\$encoded = \$encoder->encode(\$new_num , 62);

echo "<br />";

echo \$encoded." decoded is ".\$decoded = \$encoder->decode(\$encoded);
```

The result of code execution is given below:

## Simple File Searcher App: An Exercise in Concurrency

Here is a simple app for searching files on a computer. The app uses a recursive algorithm to compare names of files and folders with the search keyword and returns all the matches.

The procedure is as follows:

```1.	list the roots of the filesystem
2.	for each root listed in step1:
a.	list folders and files
b.	for each file in a., compare keyword with file name.
If matched, list this file in results
c.	for each folder in a,
i.  compare keyword with folder name.  If matched, list this folder in results
ii. repeat 2a. for each folder
d.	repeat a. to c. until no subfolders are found
```

The Java version is given below:

```/*
* To change this template file, choose Tools | Templates
* and open the template in the editor.
*/
package com.filesearch.components;

import java.io.*;
import java.io.File.*;
import java.util.concurrent.*;
import java.util.Scanner;
/**
*
* @author Dell
*/
public class FileSearcherComponent implements Runnable{

static String fileKeyword;

static long count = 0;

static File logFile;

static BufferedWriter bw;

private void logToFile(String path)
{
try{

bw.write(path, 0, path.length());
bw.newLine();

}
catch(IOException i)
{
i.printStackTrace();
}
}

@Override
public void run()
{
try{

bw = new BufferedWriter(new FileWriter(logFile, true));

}
catch(IOException i)
{
i.printStackTrace();
}

long currTime = System.currentTimeMillis();

File[] roots = File.listRoots(); //get drives

for(File root:roots)
{

File rootFile = new File(root.getPath());

traverseRoots(rootFile);
}

long endTime = System.currentTimeMillis();

double seconds = (endTime - currTime) / 1000;

System.out.printf("\n %d results in %f seconds.\n", count, seconds);

try{

bw.flush();

bw.close();
}
catch(IOException i)
{
i.printStackTrace();
}
}

private void traverseRoots(File root)
{
if(root.isDirectory())
{

String name = root.getName();

if(name.contains(fileKeyword))
{
System.out.println(root.getAbsolutePath());

logToFile(root.getAbsolutePath());

count++;
}

File[] rootFolders = root.listFiles();

if(rootFolders != null &amp;&amp; rootFolders.length &gt; 0){

for(File rootFolder: rootFolders)
{
if(rootFolder.isDirectory())
{

String name1 = rootFolder.getName();

if(name1.contains(fileKeyword))
{
System.out.println(rootFolder.getAbsolutePath());

logToFile(rootFolder.getAbsolutePath());

count++;
}

traverseRoots(rootFolder);
}
else if(rootFolder.isFile())
{
String name2 = rootFolder.getName();

if(name2.contains(fileKeyword))
{
System.out.println(rootFolder.getAbsolutePath());

logToFile(rootFolder.getAbsolutePath());

count++;
}
}

}
}
}
else if(root.isFile())
{
String name3 = root.getName();

if(name3.contains(fileKeyword))
{
System.out.println(root.getAbsolutePath());

logToFile(root.getAbsolutePath());

count++;

}
}

}

public static void main(String[] args)
{
FileSearcherComponent f = new FileSearcherComponent();

logFile = new File("LOG.txt");

if(logFile.exists())
{
logFile.delete();
}

try{

logFile.createNewFile();
}
catch(IOException i)
{
i.printStackTrace();
}

System.out.print("Enter search keyword: ");

fileKeyword  = new Scanner(System.in).nextLine();

es.execute(f);

}

}```

Copy, compile, run and ENJOY!

## Coding a game of tic-tac-toe using 3 different languages

I used a brute force logic to develop an algorithm for tic-tac-toe.
Firstly, there are only 8 triads of winning points or moves: three vertical, three horizontal and 2 diagonals.
Players play taking turns or making moves alternately. Player 1 makes a maximum of 5 moves and player
2 makes a maximum of 4 moves because there are a maximum of 9 moves to be made and player 1 begins the game.

Furthermore, player 1 has already made 2 moves before getting his first chance to form a winning line.
Players take turns alternately which means that when player 1 gets his first chance to form a line,
player 2 has already made 2 moves of his own. So player 1 can only form a line from move 5. Player 2
can only form his first line at move 6. Player 1 gets his second chance to win at move 7 and his third
and last chance at move 9. Similarly, player 2 gets his second and last chance at move 8.

Every time there is a chance to form a winning line, all possible permutations and combinations of
the current players moves, taken three at a time, are compared with all 8 winning triads. If a match is found,
the current player wins. If player 1 forms a line first, player 2 does not get a chance to continue the game.

The game has 3 versions: PHP, Java and C#

### PHP Version

It can be played via the command-line executable of your PHP installation.

In the game of tic-tac-toe there is a 3X3 grid or board.The game is for two players. The players 1 and 2 take turns to mark the cells of the grid with their mark which is a zero or a cross.

The first player to complete a vertical, horizontal or diagonal triad of zeroes or crosses, wins.

In this implementation, I have used the OOPs or Object Oriented Programming features of PHP.

I have divided the functionality and roles or responsibilities between various classes as follows.

Player makes Move on Board to play Game. So the classes are:

1. Move
2. Board
3. Player
4. Game

First we discuss the move class:

### Move:

Move made by either of the players.

```class Move
{
private \$row; // between 1 and 3
private \$column; //between 1 and 3 on the 3x3 board
private \$isValid; //whether the move is valid or not

//getters and setters for the properties
public function setRow(\$i)
{
\$this->row = \$i;
}

public function setColumn(\$j)
{
\$this->column = \$j;
}

public function setValid(\$valid)
{
\$this->isValid = \$valid;
}

public function getRow()
{
return \$this->row;
}

public function getColumn()
{
return \$this->column;
}

public function getValid()
{
return \$this->isValid;
}
}```

Then comes the Board class where the moves are made.

### Board:

The board on which the game is played.

```class Board
{
private \$cells = array(); //the 3x3 grid of cells

public function __construct()
{
\$row1 = array(" ", " ", " ");

\$row2 = array(" ", " ", " ");

\$row3 = array(" ", " ", " ");

\$this->cells[0] = \$row1;

\$this->cells[1] = \$row2;

\$this->cells[2] = \$row3;
}

//display the board with moves made so far
public function display()
{
for(\$i = 0; \$i < 3; \$i++)
{
for(\$j = 0; \$j < 3; \$j++) { if(\$this->cells[\$i][\$j] == " ")
{
echo (\$i + 1).", ".(\$j + 1)."\t";
}
else
{
echo \$this->cells[\$i][\$j]."\t";
}
}

echo "\n\n";
}
}

//check if a cell is already occupied or not
public function checkAvailable(\$move)
{
\$i = \$move->getRow();
\$j = \$move->getColumn();

\$valid1 = ((\$i >= 1 && \$i <= 3) && (\$j >= 1 && \$j <= 3));

if(\$valid1)
{
\$valid2 = (\$this->cells[\$i - 1][\$j - 1] == " ");
}
else
{
\$valid2 = false;
}

\$valid3 = (\$valid1 && \$valid2);

\$move->setValid(\$valid3);

return \$move;
}

//put a cross or zero in a cell if the move is valid
public function markCell(\$move, \$mark)
{
if(\$move->getValid())
{
\$i = \$move->getRow();
\$j = \$move->getColumn();

\$this->cells[\$i - 1][\$j - 1] = \$mark;
}
else
{
echo "INVALID MOVE!\n\n";
}
}
}```

The Player class denotes the players who make moves on the board.

### Player:

Either of the two players.

```class Player
{
private \$playerNum;  //player 1 or 2
private \$playerMark; // '0' or 'X'
private \$winnerOrLoser;
private \$moves = array(); //list of moves made by player
private \$g; //the game being played

//getters and setters
public function setPlayerNum(\$num)
{
\$this->playerNum = \$num;
}

public function setPlayerMark(\$mark)
{
\$this->playerMark = \$mark;
}

public function setPlayerWinnerLoser(\$winnerOrLoser)
{
\$this->winnerOrLoser = \$winnerOrLoser;
}

public function getPlayerNum()
{
return \$this->playerNum;
}

public function getPlayerMark()
{
return \$this->playerMark;
}

public function getPlayerWinLose()
{
return \$this->winnerOrLoser;
}

public function getPlayerMoves()
{
return \$this->moves;
}

//the player can put x or 0 by choosing the cell (row and column)
public function makeMove(\$board, \$move)
{
\$move = \$board->checkAvailable(\$move);

\$mark = \$this->getPlayerMark();
\$board->markCell(\$move, \$mark);

if(\$move->getValid())
{

\$this->getGame()->setMovesTillNow();
}

\$board->display();
}

//if move is valid, add the move to the player's list of moves
{
\$this->moves[] = \$move;
}

public function setGame(\$game)
{
\$this->g = \$game;

}

public function getGame()
{
return \$this->g;
}
}```

The Game class is the functionality of the game with all its rules.

### Game:

The game being played.

```class Game
{
private \$whoseTurn; //player 1 or 2
private static \$movesTillNow = 0; //how many moves till now
private \$gameOver; //is game over yet?
private \$winningMoves; //list of combination of moves which can win the game
private \$winner = null;

private \$winning_moves;

public function __construct()
{
//winning moves

\$this->winning_moves = array();
//row wise

\$move01 = new Move();
\$move01->setRow(1);
\$move01->setColumn(1);

\$move02 = new Move();
\$move02->setRow(1);
\$move02->setColumn(2);

\$move03 = new Move();
\$move03->setRow(1);
\$move03->setColumn(3);

\$move0 = array(\$move01, \$move02, \$move03);

\$this->winning_moves[0] = \$move0;

\$move11 = new Move();
\$move11->setRow(2);
\$move11->setColumn(1);

\$move12 = new Move();
\$move12->setRow(2);
\$move12->setColumn(2);

\$move13 = new Move();
\$move13->setRow(2);
\$move13->setColumn(3);

\$move1 = array(\$move11, \$move12, \$move13);

\$this->winning_moves[1] = \$move1;

\$move21 = new Move();
\$move21->setRow(3);
\$move21->setColumn(1);

\$move22 = new Move();
\$move22->setRow(3);
\$move22->setColumn(2);

\$move23 = new Move();
\$move23->setRow(3);
\$move23->setColumn(3);

\$move2 = array(\$move21, \$move22, \$move23);

\$this->winning_moves[2] = \$move2;

//column wise

\$move31 = new Move();
\$move31->setRow(1);
\$move31->setColumn(1);

\$move32 = new Move();
\$move32->setRow(2);
\$move32->setColumn(1);

\$move33 = new Move();
\$move33->setRow(3);
\$move33->setColumn(1);

\$move3 = array(\$move31, \$move32, \$move33);

\$this->winning_moves[3] = \$move3;

\$move41 = new Move();
\$move41->setRow(1);
\$move41->setColumn(2);

\$move42 = new Move();
\$move42->setRow(2);
\$move42->setColumn(2);

\$move43 = new Move();
\$move43->setRow(3);
\$move43->setColumn(2);

\$move4 = array(\$move41, \$move42, \$move43);

\$this->winning_moves[4] = \$move4;

\$move51 = new Move();
\$move51->setRow(1);
\$move51->setColumn(3);

\$move52 = new Move();
\$move52->setRow(2);
\$move52->setColumn(3);

\$move53 = new Move();
\$move53->setRow(3);
\$move53->setColumn(3);

\$move5 = array(\$move51, \$move52, \$move53);

\$this->winning_moves[5] = \$move5;

//diagonally

\$move61 = new Move();
\$move61->setRow(1);
\$move61->setColumn(1);

\$move62 = new Move();
\$move62->setRow(2);
\$move62->setColumn(2);

\$move63 = new Move();
\$move63->setRow(3);
\$move63->setColumn(3);

\$move6 = array(\$move61, \$move62, \$move63);

\$this->winning_moves[6] = \$move6;

\$move71 = new Move();
\$move71->setRow(1);
\$move71->setColumn(3);

\$move72 = new Move();
\$move72->setRow(2);
\$move72->setColumn(2);

\$move73 = new Move();
\$move73->setRow(3);
\$move73->setColumn(1);

\$move7 = array(\$move71, \$move72, \$move73);

\$this->winning_moves[7] = \$move7;
}

//getters and setters
public function getWhoseTurn()
{
return \$this->whoseTurn;
}

public function setWhoseTurn(\$player)
{
\$this->whoseTurn = \$player->getPlayerNum();
}

public function getGameOver()
{
return \$this->gameOver;
}

public function setGameOver(\$gameOver)
{
\$this->gameOver = \$gameOver;
}

public function setMovesTillNow()
{
self::\$movesTillNow++;
}

public function getMovesTillNow()
{
return self::\$movesTillNow;
}

public function setWinner(\$winner)
{
\$this->winner = \$winner;
}

public function getWinner()
{
return \$this->winner;
}

//check if winning moves have been made by either player
public function checkWinningMoves(\$player)
{

\$movesTillNow = \$this->getMovesTillNow();

\$whoseTurn = \$this->getWhoseTurn();

\$playerMoves = \$player->getPlayerMoves();

\$moves = \$movesTillNow;

\$winning_moves1 = \$this->winning_moves;

switch(\$whoseTurn)
{
case 1:

if(\$moves < 5)
{
return false;
}
else
{

if(\$moves == 5)
{

\$player1_set1 = array(\$playerMoves[0], \$playerMoves[1], \$playerMoves[2]);

for(\$i = 0; \$i < 8; \$i++) { if(\$this->checkSubset(\$player1_set1, \$winning_moves1[\$i]))
{
return true;
}
}

}

if(\$moves == 7)
{
\$player1_set2 = array(\$playerMoves[0], \$playerMoves[1], \$playerMoves[3]);

\$player1_set4 = array(\$playerMoves[0], \$playerMoves[2], \$playerMoves[3]);

\$player1_set7 = array(\$playerMoves[1], \$playerMoves[2], \$playerMoves[3]);

for(\$i = 0; \$i < 8; \$i++) { if(\$this->checkSubset(\$player1_set2, \$winning_moves1[\$i]) ||
\$this->checkSubset(\$player1_set4, \$winning_moves1[\$i]) ||
\$this->checkSubset(\$player1_set7, \$winning_moves1[\$i]) )
{
return true;
}
}
}

if(\$moves == 9)
{

\$player1_set3 = array(\$playerMoves[0], \$playerMoves[1], \$playerMoves[4]);

\$player1_set5 = array(\$playerMoves[0], \$playerMoves[2], \$playerMoves[4]);

\$player1_set6 = array(\$playerMoves[0], \$playerMoves[3], \$playerMoves[4]);

\$player1_set8 = array(\$playerMoves[1], \$playerMoves[2], \$playerMoves[4]);

\$player1_set9 = array(\$playerMoves[1], \$playerMoves[3], \$playerMoves[4]);

\$player1_set10 = array(\$playerMoves[2], \$playerMoves[3], \$playerMoves[4]);

for(\$i = 0; \$i < 8; \$i++) { if(\$this->checkSubset(\$player1_set3, \$winning_moves1[\$i]) ||
\$this->checkSubset(\$player1_set5, \$winning_moves1[\$i]) || \$this->checkSubset(\$player1_set6, \$winning_moves1[\$i]) ||
\$this->checkSubset(\$player1_set8, \$winning_moves1[\$i]) || \$this->checkSubset(\$player1_set9, \$winning_moves1[\$i]) ||
\$this->checkSubset(\$player1_set10, \$winning_moves1[\$i]))
{
return true;
}
}

}

return false;

}
break;
case 2:
if(\$moves < 6)
{
return false;
}
else
{
if(\$moves == 6)
{
\$player2_set1 = array(\$playerMoves[0], \$playerMoves[1], \$playerMoves[2]);

for(\$i = 0; \$i < 8; \$i++) { if(\$this->checkSubset(\$player2_set1, \$winning_moves1[\$i]))
{
return true;
}
}
}

if(\$moves == 8)
{

\$player2_set2 = array(\$playerMoves[0], \$playerMoves[1], \$playerMoves[3]);

\$player2_set3 = array(\$playerMoves[0], \$playerMoves[2], \$playerMoves[3]);

\$player2_set4 = array(\$playerMoves[1], \$playerMoves[2], \$playerMoves[3]);

for(\$i = 0; \$i < 8; \$i++) { if(\$this->checkSubset(\$player2_set2, \$winning_moves1[\$i]) || \$this->checkSubset(\$player2_set3, \$winning_moves1[\$i]) ||
\$this->checkSubset(\$player2_set4, \$winning_moves1[\$i]))
{
return true;
}
}
}

return false;

}
break;
default:
return false;
}

}

//check if player moves match the winning sequence
private function checkSubset(\$subset, \$winning_row)
{

\$count = 0;
for(\$i = 0; \$i < 3; \$i++)
{

for(\$j = 0; \$j < 3; \$j++) { if(\$subset[\$i]->getRow() == \$winning_row[\$j]->getRow() && \$subset[\$i]->getColumn() == \$winning_row[\$j]->getColumn())
{
\$count++;
}
}

}
return (\$count == 3);

}
}```

### Putting it all together.

```<?php

require("includes/move.php");  //the Move class

require("includes/player.php"); //the Player class

require("includes/board.php"); //the Board class

require("includes/game.php"); //the Game class

function main() //where all the action is
{
\$game = new Game();

\$player1 = new Player();

\$player1->setPlayerNum(1);

\$player1->setPlayerMark('X');

\$player1->setGame(\$game);

\$player2 = new Player();

\$player2->setPlayerNum(2);

\$player2->setPlayerMark('0');

\$player2->setGame(\$game);

\$b = new Board();

\$b->display();

\$game->setWhoseTurn(\$player1);

\$game->setGameOver(false);

\$status = \$game->getGameOver();

do
{
\$movesNow = \$game->getMovesTillNow();

if(\$movesNow == 9)
{

if(\$game->getWinner() == null)
{
echo "TIE!";
break;
}

}

\$turn = \$game->getWhoseTurn();

echo "PLAYER \$turn:\n\n";

\$row = 0; \$column = 0;

echo "Enter row: ";

trim(fscanf(STDIN, "%d\n", \$row));

echo "Enter column: ";

trim(fscanf(STDIN, "%d\n", \$column));

echo "\n";

\$move = new Move();

\$move->setRow(\$row);

\$move->setColumn(\$column);

switch(\$turn)
{
case 1:
\$player1->makeMove(\$b, \$move);

if(\$game->checkWinningMoves(\$player1))
{

\$game->setWinner(\$player1);

echo "PLAYER 1 WINS!\n\n";

\$game->setGameOver(true);
}
else
{
if(\$move->getValid())
{
\$movesNow = \$game->getMovesTillNow();

echo "MOVE NUMBER: \$movesNow\n\n";

\$game->setWhoseTurn(\$player2);

}
}
break;
case 2:
\$player2->makeMove(\$b, \$move);

if(\$game->checkWinningMoves(\$player2))
{

\$game->setWinner(\$player2);

echo "PLAYER 2 WINS!\n\n";

\$game->setGameOver(true);
}
else
{
if(\$move->getValid())
{
\$movesNow = \$game->getMovesTillNow();

echo "MOVE NUMBER: \$movesNow\n\n";

\$game->setWhoseTurn(\$player1);
}
}
break;
default:
echo "ERROR!\n\n";
break;
}

\$status = \$game->getGameOver();

}while(!\$status);

}

main(); //invoking the game play

?>```

This implementation is not perfect by any means. Any suggestions for improvement are welcome. Screenshots given below:

### Java Version

Here is an elementary tic-tac-toe or noughts and crosses game made in Java.
It can be played via the java interpreter from the command line. In the game of tic-tac-toe there is a 3X3 grid or board.The game is for two players. The players take turns to mark the cells of the grid with their mark which is a zero or a cross.

The first player to complete a vertical, horizontal or diagonal triad of zeroes or crosses, wins.

The PHP version can be found here

Player makes Move on Board to play Game. So the classes are:

1. Move
2. Board
3. Player
4. Game
5. TicTacToe

There is one new class “TicTacToe” because Java needs a main class having the “main” method implemented in it.

The first four classes are in the package named “com.tictactoe.components” , while the main class is in the package named “com.tictactoe”.

First we discuss the move class:

### Move:

Move made by either of the players.

```package com.tictactoe.components;

/**
*
* @author pratyush
*/
public class Move {

private int row, column;
private boolean isValid;

public int getRow() {
return row;
}

public void setRow(int row) {
this.row = row;
}

public int getColumn() {
return column;
}

public void setColumn(int column) {
this.column = column;
}

public boolean isIsValid() {
return isValid;
}

public void setIsValid(boolean isValid) {
this.isValid = isValid;
}

}```

Then comes the Board class where the moves are made.

### Board:

The board on which the game is played.

```package com.tictactoe.components;

/**
*
* @author pratyush
*/
public class Board{

private static char[][] cells;

public Board()
{
cells = new char[3][3];

cells[0] = new char[]{' ', ' ', ' '};

cells[1] = new char[]{' ', ' ', ' '};

cells[2] = new char[]{' ', ' ', ' '};
}

public void display()
{
for(int i = 0; i < 3; i++)
{
for(int j = 0; j < 3; j++) {

if(cells[i][j] == ' ') {

System.out.print((i+1)+", "+(j+1)+"\t");

} else {

System.out.print(cells[i][j]+"\t");

}

} System.out.print("\n\n");

}

}

public Move checkAvailable(Move move) {

int i = move.getRow();

int j = move.getColumn();

boolean boundValid = ((i >= 1 && i<= 3) && ( j >= 1 && j <= 3));

boolean charValid = false;

if(boundValid)
{
charValid = (cells[i - 1][j - 1] == ' ');
}

boolean netValid = (boundValid && charValid);

move.setIsValid(netValid);

return move;
}

public void markCell(Move move, char mark)
{
if(move.isIsValid())
{
int i = move.getRow();

int j = move.getColumn();

cells[i - 1][j - 1] = mark;
}
else
{
System.out.println("INVALID MOVE!\n\n");
}
}

}```

The Player class denotes the players who make moves on the board.

### Player:

Either of the two players.

```package com.tictactoe.components;

import java.util.ArrayList;
/**
*
* @author pratyush
*/
public class Player {

private int playerNum;
private char playerMark;
private int winnerOrLoser;
private Game g;

private ArrayList<Move> moves = new ArrayList<Move>();

public int getPlayerNum() {
return playerNum;
}

public void setPlayerNum(int playerNum) {
this.playerNum = playerNum;
}

public char getPlayerMark() {
return playerMark;
}

public void setPlayerMark(char playerMark) {
this.playerMark = playerMark;
}

public int getWinnerOrLoser() {
return winnerOrLoser;
}

public void setWinnerOrLoser(int winnerOrLoser) {
this.winnerOrLoser = winnerOrLoser;
}

public Game getGame() {
return g;
}

public void setGame(Game g) {
this.g = g;
}

public ArrayList getMoves() {
return moves;
}

}

public void makeMove(Board board, Move move)
{
move = board.checkAvailable(move);

char mark = this.getPlayerMark();

board.markCell(move, mark);

if(move.isIsValid())
{
Game.setMovesTillNow();
}

board.display();
}

}```

The Game class is the functionality of the game with all its rules.

### Game:

The game being played.

```package com.tictactoe.components;

import java.util.ArrayList;
/**
*
* @author pratyush
*/
public class Game{

private int whoseTurn;
private static int movesTillNow = 0;
private boolean gameOver;

private Player winner = null;

Move[][] winning_moves;

public Game()
{

winning_moves = new Move[8][3];

//top row
Move move01 = new Move();
move01.setRow(1);
move01.setColumn(1);

Move move02 = new Move();
move02.setRow(1);
move02.setColumn(2);

Move move03 = new Move();
move03.setRow(1);
move03.setColumn(3);

Move[] move0;

move0 = new Move[]{move01, move02, move03};

winning_moves[0] = move0;

//middle row

Move move11 = new Move();
move11.setRow(2);
move11.setColumn(1);

Move move12 = new Move();
move12.setRow(2);
move12.setColumn(2);

Move move13 = new Move();
move13.setRow(2);
move13.setColumn(3);

Move[] move1;

move1 = new Move[]{move11, move12, move13};

winning_moves[1] = move1;

//bottom row

Move move21 = new Move();
move21.setRow(3);
move21.setColumn(1);

Move move22 = new Move();
move22.setRow(3);
move22.setColumn(2);

Move move23 = new Move();
move23.setRow(3);
move23.setColumn(3);

Move[] move2;

move2 = new Move[]{move21, move22, move23};

winning_moves[2] = move2;

//column wise

//column 1

Move move31 = new Move();
move31.setRow(1);
move31.setColumn(1);

Move move32 = new Move();
move32.setRow(2);
move32.setColumn(1);

Move move33 = new Move();
move33.setRow(3);
move33.setColumn(1);

Move[] move3;

move3 = new Move[]{move31, move32, move33};

winning_moves[3] = move3;

//column 2

Move move41 = new Move();
move41.setRow(1);
move41.setColumn(2);

Move move42 = new Move();
move42.setRow(2);
move42.setColumn(2);

Move move43 = new Move();
move43.setRow(3);
move43.setColumn(2);

Move[] move4;

move4 = new Move[]{move41, move42, move43};

winning_moves[4] = move4;

//column 3

Move move51 = new Move();
move51.setRow(1);
move51.setColumn(3);

Move move52 = new Move();
move52.setRow(2);
move52.setColumn(3);

Move move53 = new Move();
move53.setRow(3);
move53.setColumn(3);

Move[] move5;

move5 = new Move[]{move51, move52, move53};

winning_moves[5] = move5;

//diagonals

//diagonal 1

Move move61 = new Move();
move61.setRow(1);
move61.setColumn(1);

Move move62 = new Move();
move62.setRow(2);
move62.setColumn(2);

Move move63 = new Move();
move63.setRow(3);
move63.setColumn(3);

Move[] move6;

move6 = new Move[]{move61, move62, move63};

winning_moves[6] = move6;

//diagonal 2

Move move71 = new Move();
move71.setRow(1);
move71.setColumn(3);

Move move72 = new Move();
move72.setRow(2);
move72.setColumn(2);

Move move73 = new Move();
move73.setRow(3);
move73.setColumn(1);

Move[] move7;

move7 = new Move[]{move71, move72, move73};

winning_moves[7] = move7;

}

public int getWhoseTurn() {
return whoseTurn;
}

public void setWhoseTurn(Player player) {
this.whoseTurn = player.getPlayerNum();
}

public static int getMovesTillNow() {
return movesTillNow;
}

public static void setMovesTillNow() {
Game.movesTillNow++;
}

public boolean isGameOver() {
return gameOver;
}

public void setGameOver(boolean gameOver) {
this.gameOver = gameOver;
}

public Player getWinner() {
return winner;
}

public void setWinner(Player winner) {
this.winner = winner;
}

private boolean checkSubset(Move[] subset, Move[] winning_row)
{
int count = 0;

for(int i = 0;i < 3; i++)
{
for(int j = 0; j< 3; j++)
{
if(subset[i].getRow() == winning_row[j].getRow() && subset[i].getColumn() == winning_row[j].getColumn())
{
count++;
}
}
}

return (count == 3);
}

//check the winning moves

public boolean checkWinningMoves(Player player)
{

/*****check winning moves*****/

int movesTillNow = Game.getMovesTillNow();

int whoseTurn = this.getWhoseTurn();

ArrayList<Move> playerMoves = player.getMoves();

int moves = movesTillNow;

Move[][] winning_moves1 = this.winning_moves;

switch(whoseTurn)
{
case 1:

if(moves < 5)
{
return false;
}
else
{
if(moves == 5)
{
Move[] player1_set1 = new Move[]{playerMoves.get(0), playerMoves.get(1), playerMoves.get(2)};

for(int i = 0; i< 8; i++)
{
if(checkSubset(player1_set1, winning_moves1[i]))
{
return true;
}
}
}

/******/

if(moves == 7)
{
Move[] player1_set2 = new Move[]{playerMoves.get(0), playerMoves.get(1), playerMoves.get(3)};

Move[] player1_set4 = new Move[]{playerMoves.get(0), playerMoves.get(2), playerMoves.get(3)};

Move[] player1_set7 = new Move[]{playerMoves.get(1), playerMoves.get(2), playerMoves.get(3)};

for(int i = 0; i < 8; i++)
{
if(checkSubset(player1_set2, winning_moves1[i]) ||
checkSubset(player1_set4, winning_moves1[i]) ||
checkSubset(player1_set7, winning_moves1[i]) )
{
return true;
}
}
}

if(moves == 9)
{
Move[] player1_set3 = new Move[]{playerMoves.get(0), playerMoves.get(1), playerMoves.get(4)};

Move[] player1_set5 = new Move[]{playerMoves.get(0), playerMoves.get(2), playerMoves.get(4)};

Move[] player1_set6 = new Move[]{playerMoves.get(0), playerMoves.get(3), playerMoves.get(4)};

Move[] player1_set8 = new Move[]{playerMoves.get(1), playerMoves.get(2), playerMoves.get(4)};

Move[] player1_set9 = new Move[]{playerMoves.get(1), playerMoves.get(3), playerMoves.get(4)};

Move[] player1_set10 = new Move[]{playerMoves.get(2), playerMoves.get(3), playerMoves.get(4)};

for(int i = 0; i < 8; i++)
{
if(checkSubset(player1_set3, winning_moves1[i]) ||
checkSubset(player1_set5, winning_moves1[i]) || checkSubset(player1_set6, winning_moves1[i]) ||
checkSubset(player1_set8, winning_moves1[i]) || checkSubset(player1_set9, winning_moves1[i]) ||
checkSubset(player1_set10, winning_moves1[i]))
{
return true;
}
}
}

return false;
}

case 2:
/******/
if(moves < 6)
{
return false;
}
else
{
/*******/
if(moves == 6)
{
Move[] player2_set1 = new Move[]{playerMoves.get(0), playerMoves.get(1), playerMoves.get(2)};

for(int i = 0; i < 8; i++)
{
if(checkSubset(player2_set1, winning_moves1[i]))
{
return true;
}
}
}

if(moves == 8)
{
Move[] player2_set2 = new Move[]{playerMoves.get(0), playerMoves.get(1), playerMoves.get(3)};

Move[] player2_set3 = new Move[]{playerMoves.get(0), playerMoves.get(2), playerMoves.get(3)};

Move[] player2_set4 = new Move[]{playerMoves.get(1), playerMoves.get(2), playerMoves.get(3)};

for(int i = 0; i < 8; i++)
{
if(checkSubset(player2_set2, winning_moves1[i]) || checkSubset(player2_set3, winning_moves1[i]) ||
checkSubset(player2_set4, winning_moves1[i]))
{
return true;
}
}
}

return false;
}
default:
return false;
}
}

}
```

Finally, the main class:

### TicTacToe

The class containing the entry point of the program also called the main class.

```package com.tictactoe;

import com.tictactoe.components.*;
import java.util.Scanner;
/**
*
* @author pratyush
*/
public class TicTacToe{

/**
* @param args the command line arguments
*/
public static void main(String[] args) {
// TODO code application logic here

Game game = new Game();

Player player1 = new Player();

player1.setPlayerNum(1);

player1.setPlayerMark('X');

player1.setGame(game);

Player player2 = new Player();

player2.setPlayerNum(2);

player2.setPlayerMark('0');

player2.setGame(game);

Board board = new Board();

board.display();

/*******/

game.setWhoseTurn(player1);

game.setGameOver(false);

boolean status = game.isGameOver();

Scanner sc = new Scanner(System.in);

do
{
int movesNow = Game.getMovesTillNow();

if(movesNow == 9)
{
if(game.getWinner() == null)
{
System.out.println("TIE!\n");
break;
}
}

int turn = game.getWhoseTurn();

System.out.println("PLAYER "+turn+"\n");

int row = 0;
int column = 0;

boolean invalid = true;

while(invalid)
{
//code to handle invalid moves. players cannot proceed without valid input
try{
System.out.println("Enter row: ");

String str = sc.next();

if(!str.equals(""))
{

row = Integer.parseInt(str);
invalid = false;

}
else
{
continue;
}
}
catch(NumberFormatException n)
{
System.out.println("INVALID ROW!");
invalid = true;
}
catch(InputMismatchException i)
{
System.out.println("INVALID ROW!");
invalid = true;
}
}

invalid = true;

while(invalid)
{
/*code to handle invalid moves. players cannot proceed without valid input*/

try{
System.out.println("Enter column: ");

String str = sc.next();

if(!str.equals(""))
{

column = Integer.parseInt(str);
invalid = false;

}
else
{
continue;
}
}
catch(NumberFormatException n)
{
System.out.println("INVALID COLUMN!");
invalid = true;
}
catch(InputMismatchException i)
{
System.out.println("INVALID COLUMN!");
invalid = true;
}
}

/**/

Move move = new Move();

move.setRow(row);

move.setColumn(column);

switch(turn)
{
case 1:
player1.makeMove(board, move);

if(game.checkWinningMoves(player1))
{
game.setWinner(player1);

System.out.println("PLAYER 1 WINS!");

game.setGameOver(true);
}
else
{
if(move.isIsValid())
{
movesNow = Game.getMovesTillNow();

System.out.println("MOVE NUMBER "+movesNow+"\n");

game.setWhoseTurn(player2);
}
}
break;
case 2:
player2.makeMove(board, move);

if(game.checkWinningMoves(player2))
{
game.setWinner(player2);

System.out.println("PLAYER 2 WINS!");

game.setGameOver(true);
}
else
{
if(move.isIsValid())
{
movesNow = Game.getMovesTillNow();

System.out.println("MOVE NUMBER "+movesNow+"\n");

game.setWhoseTurn(player1);
}
}
break;
default:
System.out.println("ERROR!\n");
break;
}

status = game.isGameOver();
}
while(!status);

}

}```

Copy, Compile, Run and ENJOY!

### C# version

Here is an elementary tic-tac-toe or noughts and crosses game I made in C#, arguably the most popular language of the DotNET platform. It can be played from the command line after compiling it as an executable. In the game of tic-tac-toe there is a 3X3 grid or board.The game is for two players. The players 1 and 2 take turns to mark the cells of the grid with their mark which is a zero or a cross.

The first player to complete a vertical, horizontal or diagonal triad of zeroes or crosses, wins.

The PHP version can be found here

Player makes Move on Board to play Game. So the classes are:

1. Move
2. Board
3. Player
4. Game
5. TicTacToe

There is one new class “TicTacToe” because C# needs a main class having the “Main” method implemented in it.

The classes are in the namespace called “TicTacToeDotNet”.

First we discuss the move class:

### Move:

Move made by either of the players.

```using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace TicTacToeDotNet
{
public class Move
{

private int row, column;
private bool isValid;

public int getRow()
{
return row;
}

public void setRow(int row)
{
this.row = row;
}

public int getColumn()
{
return column;
}

public void setColumn(int column)
{
this.column = column;
}

public bool isIsValid()
{
return isValid;
}

public void setIsValid(bool isValid)
{
this.isValid = isValid;
}

}
}```

Then comes the Board class where the moves are made.

### Board:

The board on which the game is played.

```using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace TicTacToeDotNet
{
public class Board
{

private static char[][] cells;

public Board()
{
cells = new char[3][];

cells[0] = new char[] { ' ', ' ', ' ' };

cells[1] = new char[] { ' ', ' ', ' ' };

cells[2] = new char[] { ' ', ' ', ' ' };
}

public void display()
{
for (int i = 0; i < 3; i++)
{
for (int j = 0; j < 3; j++) {

if (cells[i][j] == ' ') {

Console.Write((i + 1) + ", " + (j + 1) + "\t");

} else {

Console.Write(cells[i][j] + "\t");

}

} Console.Write("\n\n");

}

}

public Move checkAvailable(Move move) {

int i = move.getRow();

int j = move.getColumn();

bool boundValid = ((i >= 1 && i <= 3) && (j >= 1 && j <= 3));

bool charValid = false;

if (boundValid)
{
charValid = (cells[i - 1][j - 1] == ' ');
}

bool netValid = (boundValid && charValid);

move.setIsValid(netValid);

return move;
}

public void markCell(Move move, char mark)
{
if (move.isIsValid())
{
int i = move.getRow();

int j = move.getColumn();

cells[i - 1][j - 1] = mark;
}
else
{
Console.Write("INVALID MOVE!\n\n");
}
}

}

}```

The Player class denotes the players who make moves on the board.

### Player:

Either of the two players.

```using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace TicTacToeDotNet
{
public class Player
{

private int playerNum;
private char playerMark;
private int winnerOrLoser;
private Game g;

private List moves = new List();

public int getPlayerNum()
{
return playerNum;
}

public void setPlayerNum(int playerNum)
{
this.playerNum = playerNum;
}

public char getPlayerMark()
{
return playerMark;
}

public void setPlayerMark(char playerMark)
{
this.playerMark = playerMark;
}

public int getWinnerOrLoser()
{
return winnerOrLoser;
}

public void setWinnerOrLoser(int winnerOrLoser)
{
this.winnerOrLoser = winnerOrLoser;
}

public Game getGame()
{
return g;
}

public void setGame(Game g)
{
this.g = g;
}

public List getMoves()
{
return moves;
}

{

}

public void makeMove(Board board, Move move)
{
move = board.checkAvailable(move);

char mark = this.getPlayerMark();

board.markCell(move, mark);

if (move.isIsValid())
{
Game.setMovesTillNow();
}

board.display();
}

}
}```

The Game class is the functionality of the game with all its rules.

### Game:

The game being played.

```using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace TicTacToeDotNet
{
public class Game
{

private int whoseTurn;
private static int movesTillNow = 0;
private bool gameOver;

private Player winner = null;

Move[][] winning_moves;

public Game()
{

winning_moves = new Move[8][];

//top row
Move move01 = new Move();
move01.setRow(1);
move01.setColumn(1);

Move move02 = new Move();
move02.setRow(1);
move02.setColumn(2);

Move move03 = new Move();
move03.setRow(1);
move03.setColumn(3);

Move[] move0;

move0 = new Move[] { move01, move02, move03 };

winning_moves[0] = move0;

//middle row

Move move11 = new Move();
move11.setRow(2);
move11.setColumn(1);

Move move12 = new Move();
move12.setRow(2);
move12.setColumn(2);

Move move13 = new Move();
move13.setRow(2);
move13.setColumn(3);

Move[] move1;

move1 = new Move[] { move11, move12, move13 };

winning_moves[1] = move1;

//bottom row

Move move21 = new Move();
move21.setRow(3);
move21.setColumn(1);

Move move22 = new Move();
move22.setRow(3);
move22.setColumn(2);

Move move23 = new Move();
move23.setRow(3);
move23.setColumn(3);

Move[] move2;

move2 = new Move[] { move21, move22, move23 };

winning_moves[2] = move2;

//column wise

//column 1

Move move31 = new Move();
move31.setRow(1);
move31.setColumn(1);

Move move32 = new Move();
move32.setRow(2);
move32.setColumn(1);

Move move33 = new Move();
move33.setRow(3);
move33.setColumn(1);

Move[] move3;

move3 = new Move[] { move31, move32, move33 };

winning_moves[3] = move3;

//column 2

Move move41 = new Move();
move41.setRow(1);
move41.setColumn(2);

Move move42 = new Move();
move42.setRow(2);
move42.setColumn(2);

Move move43 = new Move();
move43.setRow(3);
move43.setColumn(2);

Move[] move4;

move4 = new Move[] { move41, move42, move43 };

winning_moves[4] = move4;

//column 3

Move move51 = new Move();
move51.setRow(1);
move51.setColumn(3);

Move move52 = new Move();
move52.setRow(2);
move52.setColumn(3);

Move move53 = new Move();
move53.setRow(3);
move53.setColumn(3);

Move[] move5;

move5 = new Move[] { move51, move52, move53 };

winning_moves[5] = move5;

//diagonals

//diagonal 1

Move move61 = new Move();
move61.setRow(1);
move61.setColumn(1);

Move move62 = new Move();
move62.setRow(2);
move62.setColumn(2);

Move move63 = new Move();
move63.setRow(3);
move63.setColumn(3);

Move[] move6;

move6 = new Move[] { move61, move62, move63 };

winning_moves[6] = move6;

//diagonal 2

Move move71 = new Move();
move71.setRow(1);
move71.setColumn(3);

Move move72 = new Move();
move72.setRow(2);
move72.setColumn(2);

Move move73 = new Move();
move73.setRow(3);
move73.setColumn(1);

Move[] move7;

move7 = new Move[] { move71, move72, move73 };

winning_moves[7] = move7;

}

public int getWhoseTurn()
{
return whoseTurn;
}

public void setWhoseTurn(Player player)
{
this.whoseTurn = player.getPlayerNum();
}

public static int getMovesTillNow()
{
return movesTillNow;
}

public static void setMovesTillNow()
{
Game.movesTillNow++;
}

public bool isGameOver()
{
return gameOver;
}

public void setGameOver(bool gameOver)
{
this.gameOver = gameOver;
}

public Player getWinner()
{
return winner;
}

public void setWinner(Player winner)
{
this.winner = winner;
}

private bool checkSubset(Move[] subset, Move[] winning_row)
{
int count = 0;

for (int i = 0; i < 3; i++)
{
for (int j = 0; j < 3; j++)
{
if (subset[i].getRow() == winning_row[j].getRow() && subset[i].getColumn() == winning_row[j].getColumn())
{
count++;
}
}
}

return (count == 3);
}

//check the winning moves

public bool checkWinningMoves(Player player)
{

/*****check winning moves*****/

int movesTillNow = Game.getMovesTillNow();

int whoseTurn = this.getWhoseTurn();

Move[] playerMoves = player.getMoves().ToArray();

int moves = movesTillNow;

Move[][] winning_moves1 = this.winning_moves;

switch (whoseTurn)
{
case 1:

if (moves < 5)
{
return false;
}
else
{
if (moves == 5)
{
Move[] player1_set1 = new Move[] { playerMoves[0], playerMoves[1], playerMoves[2] };

for (int i = 0; i < 8; i++)
{
if (checkSubset(player1_set1, winning_moves1[i]))
{
return true;
}
}
}

/******/

if (moves == 7)
{
Move[] player1_set2 = new Move[] { playerMoves[0], playerMoves[1], playerMoves[3] };

Move[] player1_set4 = new Move[] { playerMoves[0], playerMoves[2], playerMoves[3] };

Move[] player1_set7 = new Move[] { playerMoves[1], playerMoves[2], playerMoves[3] };

for (int i = 0; i < 8; i++)
{
if (checkSubset(player1_set2, winning_moves1[i]) ||
checkSubset(player1_set4, winning_moves1[i]) ||
checkSubset(player1_set7, winning_moves1[i]))
{
return true;
}
}
}

if (moves == 9)
{
Move[] player1_set3 = new Move[] { playerMoves[0], playerMoves[1], playerMoves[4] };

Move[] player1_set5 = new Move[] { playerMoves[0], playerMoves[2], playerMoves[4] };

Move[] player1_set6 = new Move[] { playerMoves[0], playerMoves[3], playerMoves[4] };

Move[] player1_set8 = new Move[] { playerMoves[1], playerMoves[2], playerMoves[4] };

Move[] player1_set9 = new Move[] { playerMoves[1], playerMoves[3], playerMoves[4] };

Move[] player1_set10 = new Move[] { playerMoves[2], playerMoves[3], playerMoves[4] };

for (int i = 0; i < 8; i++)
{
if (checkSubset(player1_set3, winning_moves1[i]) ||
checkSubset(player1_set5, winning_moves1[i]) || checkSubset(player1_set6, winning_moves1[i]) ||
checkSubset(player1_set8, winning_moves1[i]) || checkSubset(player1_set9, winning_moves1[i]) ||
checkSubset(player1_set10, winning_moves1[i]))
{
return true;
}
}
}

return false;
}

case 2:
/******/
if (moves < 6)
{
return false;
}
else
{
/*******/
if (moves == 6)
{
Move[] player2_set1 = new Move[] { playerMoves[0], playerMoves[1], playerMoves[2] };

for (int i = 0; i < 8; i++)
{
if (checkSubset(player2_set1, winning_moves1[i]))
{
return true;
}
}
}

if (moves == 8)
{
Move[] player2_set2 = new Move[] { playerMoves[0], playerMoves[1], playerMoves[3] };

Move[] player2_set3 = new Move[] { playerMoves[0], playerMoves[2], playerMoves[3] };

Move[] player2_set4 = new Move[] { playerMoves[1], playerMoves[2], playerMoves[3] };

for (int i = 0; i < 8; i++)
{
if (checkSubset(player2_set2, winning_moves1[i]) || checkSubset(player2_set3, winning_moves1[i]) ||
checkSubset(player2_set4, winning_moves1[i]))
{
return true;
}
}
}

return false;
}
default:
return false;
}
}

}
}```

Finally, the main class:

### TicTacToe

The class containing the entry point of the program also called the main class.

```using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace TicTacToeDotNet
{
public class TicTacToe
{

/**
* @param args the command line arguments
*/
public static void Main(string[] args)
{
// TODO code application logic here

Game game = new Game();

Player player1 = new Player();

player1.setPlayerNum(1);

player1.setPlayerMark('X');

player1.setGame(game);

Player player2 = new Player();

player2.setPlayerNum(2);

player2.setPlayerMark('0');

player2.setGame(game);

Board board = new Board();

board.display();

/*******/

game.setWhoseTurn(player1);

game.setGameOver(false);

bool status = game.isGameOver();

//

do
{
int movesNow = Game.getMovesTillNow();

if (movesNow == 9)
{
if (game.getWinner() == null)
{
Console.WriteLine("TIE!\n");
break;
}
}

int turn = game.getWhoseTurn();

Console.WriteLine("PLAYER " + turn + "\n");

int row = 0;
int column = 0;

bool invalid = true;

while (invalid)
{
//code to handle invalid moves. players cannot proceed without valid input
try
{
Console.WriteLine("Enter row: ");

if (!(str == ""))
{

row = Convert.ToInt32(str);
invalid = false;

}
else
{
continue;
}
}
catch (FormatException n)
{
Console.WriteLine("INVALID ROW!");
invalid = true;
}
/**/
}

invalid = true;

while (invalid)
{
/*code to handle invalid moves. players cannot proceed without valid input*/

try
{
Console.WriteLine("Enter column: ");

if (!(str == ""))
{

column = Convert.ToInt32(str);
invalid = false;

}
else
{
continue;
}
}
catch (FormatException n)
{
Console.WriteLine("INVALID COLUMN!");
invalid = true;
}
/**/
}

/**/

Move move = new Move();

move.setRow(row);

move.setColumn(column);

switch (turn)
{
case 1:
player1.makeMove(board, move);

if (game.checkWinningMoves(player1))
{
game.setWinner(player1);

Console.WriteLine("PLAYER 1 WINS!");

game.setGameOver(true);
}
else
{
if (move.isIsValid())
{
movesNow = Game.getMovesTillNow();

Console.WriteLine("MOVE NUMBER " + movesNow + "\n");

game.setWhoseTurn(player2);
}
}
break;
case 2:
player2.makeMove(board, move);

if (game.checkWinningMoves(player2))
{
game.setWinner(player2);

Console.WriteLine("PLAYER 2 WINS!");

game.setGameOver(true);
}
else
{
if (move.isIsValid())
{
movesNow = Game.getMovesTillNow();

Console.WriteLine("MOVE NUMBER " + movesNow + "\n");

game.setWhoseTurn(player1);
}
}
break;
default:
Console.WriteLine("ERROR!\n");
break;
}

status = game.isGameOver();
}
while (!status);

}

}
}```

Copy, Compile, Run and ENJOY!

## Hangman Console Game in Java and Microsoft .net

This game is a console game application based on hangman, a popular game worldwide.
There is a text file with a list of movies in it, one per line. When the game begins, the user is shown a movie title with the letters obscured by asterisks or stars.

The user is asked to guess a letter, not any non-alphabetic character. If the letter does not occur in the movie title, the player will be alerted that the guess is wrong. Also, the player will lose a chance out of a maximum of 5 chances. If all chances are gone and the movie title is still not guessed, the game is lost.

If all letters are guessed within 5 chances, the game is won. The player is then asked if he wants to continue playing the game. If yes, the game goes to another round. If not, the game exits.

The roles and functions are divided into 2 classes:

1. GetMovie: This will fetch a random movie for playing one round of the game.
2. GamePlay: Handles the playing of the game.

The code listings for these classes are given below. The game has two versions: Java and C#

## Java Version

### Get Movie Class

```/*
* To change this template file, choose Tools | Templates
* and open the template in the editor.
*/
package com.Hangman;

import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;

/**
*
*
*/
public class GetMovie {

static ArrayList movies = new ArrayList();

static String movie;

static String path;

GetMovie(String pathToFile)
{
path = pathToFile;
}

public static String getRandMovie()
{
String randWord = "";
try{

InputStream istream = new FileInputStream(path);

String movie;

{
}

int size = movies.size();

int idx = (new java.util.Random()).nextInt(size);

randWord = movies.get(idx);

}
catch(FileNotFoundException f)
{
System.out.println(f.getMessage());

System.exit(0);
}
catch(IOException io)
{
System.out.println(io.getMessage());

System.exit(0);
}

return randWord;
}

}```

### GamePlay Class

```/*
* To change this template file, choose Tools | Templates
* and open the template in the editor.
*/
package com.Hangman;

import java.util.Scanner;

/**
*
*
*/
public class GamePlay {

static char[] movieChars;
static char[] guessChars;
static int chances = 5;

static void renderMovie(String movie)
{
movieChars = movie.toCharArray();

guessChars = new char[movieChars.length];

for(int i = 0; i&lt; movieChars.length; i++)
{
if(Character.isLetter(movieChars[i]))
{
System.out.print("* ");
}
else
{
System.out.print(movieChars[i] + " ");

guessChars[i] = movieChars[i];

}
}

System.out.println();
}

private static boolean playChar(char ch)
{
int matchCount = 0;

for(int i = 0; i &lt; movieChars.length; i++)
{
if(Character.toLowerCase(movieChars[i]) == Character.toLowerCase(ch))
{
matchCount++;

guessChars[i] = movieChars[i];
}
}

if(matchCount == 0)
{
chances--;

System.out.println("WRONG Guess! You have "+chances+" chances left!");
}

/**/

for(int i = 0; i&lt; guessChars.length; i++)
{
if(guessChars[i] == '\0')
{
System.out.print("* ");
}
else
{
System.out.print(guessChars[i]+ " ");
}
}

System.out.println();

String movie = new String(movieChars);

String guessed = new String(guessChars);

return movie.equals(guessed);

}

public static void main(String[] args)
{
GetMovie gm = new GetMovie("movies.txt");

char choice = '\0';

System.out.println("/***************WELCOME TO JAVA HANGMAN**************/");

do{

chances = 5;

String movie = GetMovie.getRandMovie();

renderMovie(movie);

System.out.print("Enter a letter: ");

Scanner sc = new Scanner(System.in);

char gchar = sc.next().charAt(0);

while(!playChar(gchar))
{
if(chances == 0)
{
break;
}

System.out.print("Enter a letter: ");

sc = new Scanner(System.in);

gchar = sc.next().charAt(0);
}

if(chances == 0)
{
System.out.println("You LOSE! The movie was: \n"+movie);
}
else
{
System.out.println("You WIN!");
}

System.out.print("\nPlay again (y/n)?: ");

sc = new Scanner(System.in);

choice = sc.next().charAt(0);

}
while(choice == 'y' || choice == 'Y');

System.out.println("EXITING...");
System.exit(0);
}

}```

Copy, compile, run and ENJOY!

## C# Version

```using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace ConsoleHangman
{
class GetMovie
{
private static List lines = new List();

static string movie;

static string path;

public GetMovie(string pathToFile)
{
path = pathToFile;
}

internal static string getRandMovie()
{

string line;

while ((line = file.ReadLine()) != null)
{
}

int count = lines.Count;

Random r = new Random();

int index = r.Next(count);

string line1 = lines[index];

file.Close();

return line1; //working
}
}

class GamePlay
{
static char[] movieChars;
static char[] guessChars;
static int chances = 5;

static void renderMovie(String movie)
{
movieChars = movie.ToCharArray();

guessChars = new char[movieChars.Length];

for (int i = 0; i &lt; movieChars.Length; i++)
{
if (Char.IsLetter(movieChars[i]))
{
Console.Write("* ");
}
else
{
Console.Write(movieChars[i] + " ");

guessChars[i] = movieChars[i];

}
}

Console.WriteLine();
}

private static bool playChar(char ch)
{
int matchCount = 0;

for (int i = 0; i &lt; movieChars.Length; i++)
{
if (Char.ToLower(movieChars[i]) == Char.ToLower(ch))
{
matchCount++;

guessChars[i] = movieChars[i];
}
}

if (matchCount == 0)
{
chances--;

Console.WriteLine("WRONG Guess! You have " + chances + " chances left!");
}

/**/

for (int i = 0; i &lt; guessChars.Length; i++)
{
if (guessChars[i] == '\0')
{
Console.Write("* ");
}
else
{
Console.Write(guessChars[i] + " ");
}
}

Console.WriteLine();

string movie = new string(movieChars);

string guessed = new string(guessChars);

return (movie == guessed);

}

public static void Main(string[] args)
{
GetMovie gm = new GetMovie("..\\..\\movies.txt");

char choice = '\0';

Console.WriteLine("/***************WELCOME TO C# HANGMAN**************/");

do
{

chances = 5;

String movie = GetMovie.getRandMovie();

renderMovie(movie);

Console.Write("Enter a letter: ");

while (!playChar(gchar))
{
if (chances == 0)
{
break;
}

Console.Write("Enter a letter: ");

}

if (chances == 0)
{
Console.WriteLine("You LOSE! The movie was: \n" + movie);
}
else
{
Console.WriteLine("You WIN!");
}

Console.Write("\nPlay again (y/n)?: ");

}
while (choice == 'y' || choice == 'Y');

Console.WriteLine("Press a key to exit...");
}
}
}
```

See the video below. COPY, COMPILE, RUN and ENJOY!

## PHP Web Services: What they are, what they do and how to make one.

A “Web Service” is a bunch of code that resides on a server in an intranet or the internet. It performs some function and returns some data required by the client application that calls it. e.g. A foreign exchange web service might return the rates at which euros are converted to US dollars. A weather web service will return local temperature during any day. These web services can then be used in client applications like an e-commerce site that shows product prices in euros or dollars depending on the country the buyer is in, etc.

One common use of web services is in smartphone apps as a backend. A smartphone does not typically query a site’s database directly since it is not good to store database credentials locally on it. So the app calls a web service residing on a server. This web service fetches data from a web application and returns the data found to the smartphone app. e.g. An mobile e-commerce store allows users to search products by keywords. This app will call a web service which acts like a function that will accept the search keyword as a parameter. The web service returns a list of products to the calling app either as JSON or XML. The calling app will parse the results and display a list of products with names and images to the buyer.

But how is this achieved from the coding standpoint ? How does one create a PHP web service? There are many ways but I shall discuss about SOAP-based web services and illustrate with an example containing both the web service and the calling code in PHP. I will be using the NUSOAP library in my example. This will be an parameterized hello world web service. The client will call the web service and pass a name as a parameter to it. The result will be a
“Hello” greeting to the name given.

We need to do two things, (1) Setup the server side and (2) Setup the client side, from which we will call our web service.

DISCLAIMER: It is assumed that the reader knows basics of PHP development and can work on web servers or locally setup development servers.

## Setting Up The Server Side

1. Check SOAP is enabled on the server: Your server phpinfo() should look like this.If your phpinfo() does not look like the screenshot above, you need to locate your php.ini file and uncomment the semi-colon in the lines containing the soap DLL file (php_soap.dll in Windows). Save the modified php.ini and restart Apache Server. Then check your phpinfo() again.
2. Create a new project folder on server.
4. Extract the archive and keep the lib folder in your project folder.
5. Call lib/nusoap.php in your PHP file where you will be working.
`<?php require('lib/nusoap.php'); //make sure that the nusoap.php file is found at this path relative to your php source file ?>`
6. Create a SOAP server object.
`<?php \$soapServer = new soap_server(); //create the soap server object ?>`
7. Configure WSDL
`<?php \$soapServer-&gt;configureWSDL("HelloWorldWSDL", "http://www.helloworldsite.com"); //configure the WSDL ?>`
8. Register a method with your SOAP server.
`<?php \$soapServer-&gt;register('helloWorldWebSvc', array('name'=&gt;'xsd:string'),array('return'=&gt;"xsd:string"), "http://www.helloworldsite.com", "http://www.helloworldsite.com#helloWorldWebSvc", 'rpc', 'encoded', 'Hello World App!'); //register the method with the server ?>`
9. Make sure you call the service method of the SOAP server.
`<?php /*\$soapServer-&gt;service(\$HTTP_RAW_POST_DATA); //Fault:SOAP-ENV:Client error in msg parsing: xml was empty, didn't parse! */ @\$soapServer-&gt;service(file_get_contents("php://input")); //FIXED ?>`
10. ##### Putting It All Together
```<?php

require("lib/nusoap.php");

\$soapServer = new soap_server(); //create the soap server object

\$soapServer->configureWSDL("HelloWorldWSDL", "http://www.helloworldsite.com"); //configure the WSDL

\$soapServer->register('helloWorldWebSvc', array('name'=&amp;gt;'xsd:string'),array('return'=&amp;gt;"xsd:string"), "http://www.helloworldsite.com", "http://www.helloworldsite.com#helloWorldWebSvc", 'rpc', 'encoded', 'Hello World App!'); //register the method with the server

function helloWorldWebSvc(\$name) //our function with business logic. Also called the server-side method.
{ return "Hello \$name!"; }

\$HTTP_RAW_POST_DATA = isset(\$HTTP_RAW_POST_DATA)?\$HTTP_RAW_POST_DATA:'';
/*\$soapServer->service(\$HTTP_RAW_POST_DATA); //Fault:SOAP-ENV:Client error in msg parsing: xml was empty, didn't parse! */

@\$soapServer->service(file_get_contents("php://input")); //FIXED

exit; ?>```

### Important Note

It is important to note that there are outdated code snippets out there using \$soapServer->service(\$HTTP_RAW_POST_DATA);

This wont work with NUSOAP in PHP 7. It will give the error:

Fault:SOAP-ENV:Client error in msg parsing: xml was empty, didn’t parse!

Fix it by using the following:

@\$soapServer->service(file_get_contents(“php://input”));

## Setting Up the Client Side

1. Check SOAP is enabled on the server: This step is identical to its counterpart in the server-side above.
2. Create a new project folder on server: This step is identical to its counterpart in the server-side above.
3. Install the PHP NUSOAP library: This step is identical to its counterpart in the server-side above.
4. Call lib/nusoap.php in your PHP file where you will be working: This step is identical to its counterpart in the server-side above.
5. Create a SOAP client object.
`<?php \$client = new nusoap_client("http://localhost/HelloSvc/hello_world_web_svc.php?wsdl"); ?>`
6. Call the server-side method.
`<?php \$response = \$client-&gt;call("helloWorldWebSvc", array("Some User")); //calling the registered method of the web service from client. ?>`
7. ##### Putting It All Together
```<?php

require("lib/nusoap.php");

\$client = new nusoap_client("http://localhost/HelloSvc/hello_world_web_svc.php?wsdl");

\$response = \$client->call("helloWorldWebSvc", array("Some User")); //calling the registered method of the web service from client

if(\$client->fault) {

echo "Fault:".\$client->faultcode." ".\$client->faultstring;

} else {

print_r(\$response);

}

exit;

?>```

Note: In Android and iOS apps, no PHP client is used generally. Instead coding is done in Java or Objective-C, etc that uses the HTTP Client API of the respective programming languages.

## The End Result

If all goes well you will see a screen like the one below when you invoke the PHP Web Service client in your browser.

Note: This example is compliant with PHP 7.

## Cows and Bulls: A simple word guessing game

“Cows and Bulls” is a simple word guessing game. In the beginning, the player is told how many letters there are in the word to guess. This is indicated by the number of stars or asterisks displayed. Then the player guesses the word. If the guess is correct, the player is declared a winner and is then prompted to continue or end the game.

If not, the player is told how many hits or “bulls” he made and how many misses or “cows” he made. The player is also asked if he wants to give up.If not, he must continue playing. If he gives up, he will be told what the word was. He will then be prompted to continue or end the game.

One of the subroutines in this program retrieves a random word from a dictionary file which is essentially a text file containing one word per line. It stores all the words in a list and then picks a random element based on the size of the list.

This game has 2 versions: Java and C#

### Java Version

```/*
* To change this template file, choose Tools | Templates
* and open the template in the editor.
*/
package com.cowsandbulls;

import java.io.*;
import java.util.*;
/**
*
* @author Dell
*/
public class CowsAndBulls {

static ArrayList words = new ArrayList();

private static String getRandWord(String path)
{
String randWord = "";

try{

InputStream istream = new FileInputStream("words.txt");

String word;

{
}

int size = words.size();

int idx = (new java.util.Random()).nextInt(size);

randWord = words.get(idx);

}
catch(FileNotFoundException f)
{
System.out.println(f.getMessage());

System.exit(0);
}
catch(IOException io)
{
System.out.println(io.getMessage());

System.exit(0);
}

return randWord;
}

public static void main(String[] args)
{
char cont = '\0';

Scanner sc  = new Scanner(System.in);

System.out.println("WELCOME TO COWS AND BULLS!\n");

do{

String w = getRandWord("words.txt"); //ok
//System.out.println(w);

char[] guessChars = w.toCharArray();

char giveUp = '\0';

for(int i = 0; i&lt; w.length(); i++)
{
System.out.print("* ");
}

System.out.println("\n");

do
{

System.out.print("Guess the word: ");

String guess = sc.nextLine();

if(guess.equals(w))
{
System.out.println("YOU WIN!\n");

break;
}
else
{

if(guess.length() == w.length())
{
int cows = 0, bulls = 0;

for(int i = 0;i &lt; w.length(); i++)
{
if(w.charAt(i) == guess.charAt(i))
{
bulls++;

System.out.print("bull ");
}
else
{
cows++;

System.out.print("cow ");
}
}

System.out.println();

System.out.println(bulls + " bulls, "+cows+" cows.\n");
}
else
{
System.out.println("LENGTH MISMATCH!");
}

System.out.println("Do you give up? (y/n): ");

String s = sc.nextLine();

while(s.length() == 0)
{
System.out.println("Do you give up? (y/n): ");
s = sc.nextLine();
}

giveUp = s.charAt(0);

//giveUp = sc.nextLine().charAt(0);

}
}
while(giveUp != 'y' &amp;&amp; giveUp != 'Y');

if(giveUp == 'y' || giveUp == 'Y')
{
System.out.println("The word was: "+w);
}

System.out.println("Continue? (y/n): ");

String s = sc.nextLine();

while(s.length() == 0)
{
System.out.println("Continue? (y/n): ");
s = sc.nextLine();
}

//

cont = s.charAt(0);

}while(cont == 'y' || cont == 'Y');

System.out.println("Press any key to exit...");

/* */

System.exit(0);

}

}
```

Copy, compile, run and ENJOY!

### C# Version

The code is in the listing.
Also, see the video below.

```using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace CowsAndBulls
{
class Program
{

private static List lines = new List();

private static string GetWordFromFile(string path)
{

string line;

while ((line = file.ReadLine()) != null)
{
}

int count = lines.Count;

Random r = new Random();

int index = r.Next(count);

string line1 = lines[index];

file.Close();

return line1; //working
}

static void Main(string[] args)
{
//

char cont = '\0';

Console.WriteLine("WELCOME TO COWS AND BULLS!\n");

do
{

string w = GetWordFromFile("..\\..\\words.txt"); //ok

char[] guessChars = w.ToCharArray();

char giveUp = '\0';

//

for (int i = 0; i &lt; w.Length; i++)
{
Console.Write("* ");
}

Console.WriteLine("\n");

do
{

Console.Write("Guess the word: ");

if (guess == w)
{
Console.WriteLine("YOU WIN!\n");

break;
}
else
{

if (guess.Length == w.Length)
{
int cows = 0, bulls = 0;

for (int i = 0; i &lt; w.Length; i++)
{
if (w.Substring(i, 1) == guess.Substring(i, 1))
{
bulls++;

Console.Write("bull ");
}
else
{
cows++;

Console.Write("cow ");
}
}

Console.WriteLine();

Console.WriteLine(bulls + " bulls, " + cows + " cows.\n");
}
else
{
Console.WriteLine("LENGTH MISMATCH!");
}

Console.WriteLine("Do you give up? (y/n): ");

while (s.Length == 0)
{
Console.WriteLine("Do you give up? (y/n): ");
}

giveUp = Convert.ToChar(s.Substring(0, 1));

//

}
}
while (giveUp != 'y' &amp;&amp; giveUp != 'Y');

if (giveUp == 'y' || giveUp == 'Y')
{
Console.WriteLine("The word was: " + w);
}

Console.WriteLine("Continue? (y/n): ");

while (s1.Length == 0)
{
Console.WriteLine("Continue? (y/n): ");
}

//

cont = Convert.ToChar(s1.Substring(0, 1));

} while (cont == 'y' || cont == 'Y');

Console.WriteLine("Press any key to exit...");

}
}
}```

Copy, compile, run and ENJOY!

## My WordPress Plugin for Customer Reviews

Welcome to my site! I have just posted my wordpress plugin named eazy123 customer reviews.

The demo can be found here. Its salient features include not asking reviewers their email

addresses and a five-star rating system.

Take it out for a test drive. Screenshots given below. Hope you like it!