life.php

<?php

// Implementation of Conway's game of life in PHP
// Incomplete and buggy ;)

$board = "
-------------------
-------------------
-------------------
-------------------
-------------------
-------------------
--------***--------
--------*-*--------
--------***--------
--------***--------
--------***--------
--------***--------
--------***--------
--------*-*--------
--------***--------
-------------------
-------------------
-------------------
-------------------
-------------------
-------------------
";

function read_board($board) {
    $lines = explode("\n", trim($board));
    $w = strlen($lines[0]);
    $a = [];
    foreach($lines as $l) {
        $k = [];
        for($i = 0; $i < $w; $i++)
            $k[] = $l[$i] == '*' ? 1 : 0;
        $a[] = $k;
    }
    return $a;
}

function write_board($a) {
    foreach($a as $l) {
        foreach($l as $b)
            echo $b ? '*' : '-';
        echo "\n";
    }
}

function play($a) {
    $b = [];
    $w = sizeof($a[0]);
    for($y = 0, $h = sizeof($a); $y < $h; $y++)
        for($x = 0, $ww = $w; $x < $w; $x++) {
            $c = $a[$y][$x];
            $n = @$a[$y-1][$x-1] + @$a[$y-1][$x] + @$a[$y-1][$x+1] +
                 @$a[$y][$x-1]                   + @$a[$y][$x+1]   +
                 @$a[$y+1][$x-1] + @$a[$y+1][$x] + @$a[$y+1][$x+1];
            if($c && $n < 2)
                $c = false;
            elseif($c && $n > 3)
                $c = false;
            elseif($c)
                $c = true;
            elseif(!$c && $n == 3)
                $c = true;
            $b[$y][$x] = $c;
        }
    return $b;
}

$a = read_board($board);

while(1) {
    write_board($a);
    echo "\n";
    $a = play($a);
    sleep(1);
}