PrimeGame Java Sourcecode Board Game for 2 Players • The board has n fields, initially filled with natural numbers from 1 to n. • Each number on the board represents its score. • The goal is to get a higher total score than the opponent. • In turns, the players take (available) numbers off the board - and receive the score of the number they took. • However, when the taken number has dividing numbers left on the board, those divisors are also taken of the board and give their score to the opponent immediately. Rules and Constraints • The moving player must always return a number still available on the board. • A player must have completed a move in less than 500ms. • No file write-access is permitted (read-only access is allowed) • No GUI classes may be used (e.g. Swing, AWT, SWT, etc.) • 3rd-Party Libraries (e.g. Math libraries, etc.) may be used. Example Game with a Board Size of 20 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 • Player A starts the game and chooses... 19. • The only number on the board dividing 19 is 1, so player B gets 1. • Now it's player B to move... • Player B is greedy and chooses 20... • This, however, gives player A all remaining divisors of 20 on the board: 2, 4, 5 and 10. • Thus, player A actually gets more points from the divisors, than player B got from his own move. Bad Move by Player B! • Player A chooses 18. • Player B gets 3, 6 and 9. • Player B chooses 17. • Player A gets nothing No dividors of 17 on the board (1 is already taken). • Player A chooses 15. • Player B gets nothing (3 and 5 are both already taken). • Player B chooses 16. • Player A gets 8. • Player A chooses 13. • Player B gets nothing. • Player B chooses 12. • Player A gets nothing. • Player A chooses 11. • Player B gets nothing. • Player B chooses 14. • Player A gets 7. • No more numbers left on the board. Game over! Player Score Total Player A 2 + 4 + 5 + 7 + 8 + 10 + 11 + 13 + 15 + 18 + 19 112 Player B 1 + 3 + 6 + 9 + 12 + 14 + 16 + 17 + 20 98 ! Player A wins the game. The PrimeGame Framework • Set up a clean board for each match. • Select a pair of players to compete against each other. • “Show" the board to the player whose turn it is. • Let the player choose a number from the board. • Find the divisors. • Assign the proper score to both players. • Keep track of all player's scores and rankings. • Enforce resource constraints (e.g. time limits).

I got stucked after implementing the following code: package primegame . player ; import java . util . Set ; public interface Player { abstract public String getPlayerName (); abstract public Integer makeMove (Set < Integer > availableNumbers ); abstract public void setScore ( int playerScore , int opponentScore ); } package primegame . player . samples ; import java . util .*; import primegame . player . Player ; public class GreedyPlayer implements Player { public Integer makeMove ( Set < Integer > board ) { int highest = Integer . MIN_VALUE ; for ( Iterator < Integer > it = board . iterator (); i. hasNext (); ) { int n = it. next (); if (n > highest ) highest = n; } return highest ; } public String getPlayerName () { return " Garry Greedy "; } public void setScore ( int playerScore , int opponentScore ) {} } public Integer makeMove ( Set < Integer > board ) { int highestPrime = Integer . MIN_VALUE ; for ( Iterator < Integer > it = board . iterator (); i. hasNext (); ) { int n = it. next (); if ( n > highestPrime && n >= 3 ) { boolean isPrime = true ; for ( int j = 3; j <= Math . ceil ( Math . sqrt ( n ) ); j++ ) if ( n % j == 0 ) { isPrime = false ; break ; } if ( isPrime ) { highestPrime = n; } } } if ( highestPrime != Integer . MIN_VALUE ) { return highestPrime ; } else { Integer [] nrs = availableNumbers . toArray ( new Integer [ availableNumbers . size ()] ); return nrs [new Random (). nextInt ( nrs . length )]. intValue (); } }

I got stucked after implementing the following code: package primegame . player ; import java . util . Set ; public interface Player { abstract public String getPlayerName (); abstract public Integer makeMove (Set < Integer > availableNumbers ); abstract public void setScore ( int playerScore , int opponentScore ); } package primegame . player . samples ; import java . util .*; import primegame . player . Player ; public class GreedyPlayer implements Player { public Integer makeMove ( Set < Integer > board ) { int highest = Integer . MIN_VALUE ; for ( Iterator < Integer > it = board . iterator (); i. hasNext (); ) { int n = it. next (); if (n > highest ) highest = n; } return highest ; } public String getPlayerName () { return " Garry Greedy "; } public void setScore ( int playerScore , int opponentScore ) {} } public Integer makeMove ( Set < Integer > board ) { int highestPrime = Integer . MIN_VALUE ; for ( Iterator < Integer > it = board . iterator (); i. hasNext (); ) { int n = it. next (); if ( n > highestPrime && n >= 3 ) { boolean isPrime = true ; for ( int j = 3; j <= Math . ceil ( Math . sqrt ( n ) ); j++ ) if ( n % j == 0 ) { isPrime = false ; break ; } if ( isPrime ) { highestPrime = n; } } } if ( highestPrime != Integer . MIN_VALUE ) { return highestPrime ; } else { Integer [] nrs = availableNumbers . toArray ( new Integer [ availableNumbers . size ()] ); return nrs [new Random (). nextInt ( nrs . length )]. intValue (); } }