# Snake And Ladder

*is a*

**Snake And Ladder****draft**programming task. It is not yet considered ready to be promoted as a complete task, for reasons that should be found in its talk page.

Let us create a Snakes and Ladders game where the computer plays against a human player.

For a board example you can use this image here: snakes & ledders.

The way you'll represent the board and the players' tokens is totally up to you: graphics or ASCII graphics or even just text.

Happy coding.

## Perl 6[edit]

Snakes and ladders is entirely chance based, so human interaction is not really required. This version allows up to one human player against any number of computer players and asks for input... but doesn't really *need* or even *use* it. I didn't bother to implement a graphical interface.

# board layout

my %snl = 4, 14, 9, 31, 17, 7, 20, 38, 28, 84, 40, 59, 51, 67, 54, 34,

62, 19, 63, 81, 64, 60, 71, 91, 87, 24, 93, 73, 95, 75, 99, 78;

my @players = 1, 1, 1; # three players, starting on square 1

my $human = 1; # player 1 is human. set to 0 for all computer players

loop {

for ^@players -> $player {

turn(@players[$player], $player + 1);

}

say '';

}

sub turn ($square is rw, $player) {

if $player == $human {

prompt "You are on square $square. Hit enter to roll the die.";

}

my $roll = (1..6).roll;

my $turn = $square + $roll;

printf "Player $player on square %2d rolls a $roll", $square;

if $turn > 100 {

say " but cannot move. Next players turn.";

return $square;

}

if %snl{$turn} {

$square = %snl{$turn};

if $turn > $square {

say ". Oops! Landed on a snake. Slither down to $square."

} else {

say ". Yay! Landed on a ladder. Climb up to $square."

}

} else {

$square = $turn;

say " and moves to square $square";

}

say "Player $player wins!" and exit if $square == 100;

return $square;

}

- Sample output:

You are on square 1. Hit enter to roll the die. Player 1 on square 1 rolls a 1 and moves to square 2 Player 2 on square 1 rolls a 4 and moves to square 5 Player 3 on square 1 rolls a 1 and moves to square 2 You are on square 2. Hit enter to roll the die. Player 1 on square 2 rolls a 1 and moves to square 3 Player 2 on square 5 rolls a 2 and moves to square 7 Player 3 on square 2 rolls a 3 and moves to square 5 You are on square 3. Hit enter to roll the die. Player 1 on square 3 rolls a 4 and moves to square 7 Player 2 on square 7 rolls a 1 and moves to square 8 Player 3 on square 5 rolls a 2 and moves to square 7 You are on square 7. Hit enter to roll the die. Player 1 on square 7 rolls a 2. Yay! Landed on a ladder. Climb up to 31. Player 2 on square 8 rolls a 3 and moves to square 11 Player 3 on square 7 rolls a 2. Yay! Landed on a ladder. Climb up to 31. ... about 15 turns omitted ... You are on square 90. Hit enter to roll the die. Player 1 on square 90 rolls a 3. Oops! Landed on a snake. Slither down to 73. Player 2 on square 55 rolls a 3 and moves to square 58 Player 3 on square 90 rolls a 4 and moves to square 94 You are on square 73. Hit enter to roll the die. Player 1 on square 73 rolls a 6 and moves to square 79 Player 2 on square 58 rolls a 5. Yay! Landed on a ladder. Climb up to 81. Player 3 on square 94 rolls a 3 and moves to square 97 You are on square 79. Hit enter to roll the die. Player 1 on square 79 rolls a 3 and moves to square 82 Player 2 on square 81 rolls a 6. Oops! Landed on a snake. Slither down to 24. Player 3 on square 97 rolls a 5 but cannot move. Next players turn. You are on square 82. Hit enter to roll the die. Player 1 on square 82 rolls a 5. Oops! Landed on a snake. Slither down to 24. Player 2 on square 24 rolls a 6 and moves to square 30 Player 3 on square 97 rolls a 4 but cannot move. Next players turn. You are on square 24. Hit enter to roll the die. Player 1 on square 24 rolls a 4. Yay! Landed on a ladder. Climb up to 84. Player 2 on square 30 rolls a 5 and moves to square 35 Player 3 on square 97 rolls a 4 but cannot move. Next players turn. You are on square 84. Hit enter to roll the die. Player 1 on square 84 rolls a 1 and moves to square 85 Player 2 on square 35 rolls a 2 and moves to square 37 Player 3 on square 97 rolls a 3 and moves to square 100 Player 3 wins!

## Ruby[edit]

NONE = 0; LADDER = 1; SNAKE = 2; STAY = 1; MOVE = 2; WIN = 3

class Cell

@type; @to; attr_reader :type, :to

def initialize; @type = NONE; @to = 0; end

def set( t, o ); @type = t; @to = o; end

end

class Player

@pos; @name; attr_accessor :pos; attr_reader :name

def initialize( n ); @pos = 0; @name = n; end

def play( dice )

s = dice.roll; return s, STAY if @pos + s > 99

@pos += s; return s, WIN if @pos == 99

return s, MOVE

end

end

class Die

@sides; def initialize( s = 6 ); @sides = s; end

def roll; return 1 + rand( @sides ); end

end

def initBoard

@board = Array.new( 100 ); for i in 0 .. 99; @board[i] = Cell.new(); end

@board[3].set( LADDER, 13 ); @board[8].set( LADDER, 30 ); @board[19].set( LADDER, 37 );

@board[27].set( LADDER, 83 );@board[39].set( LADDER, 58 ); @board[50].set( LADDER, 66 );

@board[62].set( LADDER, 80 ); @board[70].set( LADDER, 90 ); @board[16].set( SNAKE, 6 );

@board[61].set( SNAKE, 18 ); @board[86].set( SNAKE, 23 ); @board[53].set( SNAKE, 33 );

@board[63].set( SNAKE, 59 ); @board[92].set( SNAKE, 72 ); @board[94].set( SNAKE, 74 );

@board[98].set( SNAKE, 77 );

end

def initPlayers

@players = Array.new( 4 );

for i in 0 .. @playersCount - 1; @players[i] = Player.new( "player " << i + 49 ); end

end

def play

initBoard; initPlayers; @die = Die.new

while true

for p in 0 .. @playersCount - 1

puts; puts

if( 0 == p )

print "[email protected][p].name}, your turn. Your position is cell [email protected][p].pos + 1}.\n"<<

"Press [RETURN] to roll the die."

gets; np = @players[p].play( @die ); print "You rolled a #{np[0]}\n"

if np[1] == WIN

print "You reached position [email protected][p].pos + 1} and win the game!!!!\n"; return

elsif np[1] == STAY; print "Sorry, you cannot move!\n"

else print "Your new position is cell [email protected][p].pos + 1}.\n";

end

else

np = @players[p].play( @die ); print "[email protected][p].name} rolled a #{np[0]}.\n"

if np[1] == WIN

print "He reached position [email protected][p].pos + 1} and wins the game!!!!\n"; return

elsif np[1] == STAY; print "But he cannot move....\n"

else print "His new position is cell [email protected][p].pos + 1}.\n";

end

end

s = @board[@players[p].pos].type

next if s == NONE

@players[p].pos = @board[@players[p].pos].to

case s

when SNAKE; print "What a pitty, landed on a snake. "

when LADDER; print "Lucky move! Landed on a ladder. "

end

print "New position is cell [email protected][p].pos + 1}.\n"

end

end

end

@playersCount = 4; @board; @players; @die

play

- Output:

... player 1, your turn. Your position is cell 97. Press [RETURN] to roll the die. You rolled a 5 Sorry, you cannot move!

player 2 rolled a 5. His new position is cell 49.

player 3 rolled a 4. But he cannot move....

player 4 rolled a 6. His new position is cell 91.

player 1, your turn. Your position is cell 97. Press [RETURN] to roll the die. You rolled a 3 You reached position 100 and win the game!!!!