UNSW ProgComp: Problem 4 - 2007

<?php

$input = <<<END
9
17 11
8 1
5 4
29 2
50 49
18 6
37 3
2 1
41 3
END;

function generate_array($length){
    for($x = 0; $x < $length; $x++){
        $new_array[$x] = array($x, 0); //this is kinda silly, but it works
            //value, status 0=alive 1=dead (counter intuitive but meh)
    }
    //print_r($new_array);
    return $new_array;
}

$input = explode("\n", $input);
array_shift($input); //scrap the frist line

foreach($input as $key => $value){
    $input[$key] = explode(" ", $value);
}

foreach($input as $key => $value){
    //value[0] = count of people
    //value[1] = jump length

    /*
    0 - 1 - kill loop 4
    1 - 2 - kill loop 2
    2 - 3 - kill loop 1
    3 - 4 - survivor
    4 - 5 - kill loop 3
    5 - 6 - kill loop 1
    6 - 7 - kill loop 2

    if jump is three,
    start counting at zero, add 2 (k - 1) to that number (0 + k - 1 (0 + 3 - 1 = 2)), remove that number from the list
    (destroy key 2), add 2 + 1 + 3 - 1 (last_pos + 1 + k - 1)%n = 5. then: last_pos = 5, n = 7 so (5+1 + 3-1)%7 = (8)%7 = 1

    wait... that system is stupid, let's do it the rudamentary way
    couple of while loops
    */
    $array = generate_array($value[0]); //of length 'n'
    $header = 0;
    $kills = 0;
    $jump_length = $value[1];
    $total = $value[0];

    while(($total - $kills) > 1){
        $jumping = $jump_length;
        while($jumping != 1){
            if($array[$header][1] == 0){
                //decrement jumping
                $jumped = $array[$header][0];
                $jumping--;
                //echo "Jumping: $jumped\n";
            }else{
                $jumped = $array[$header][0];
                //echo "Already dead: $jumped\n";
            }
            $header++;
            $header = $header%$total;
        }
        //the next value where array[x][1] == 0 gets killed
        while($array[$header][1] != 0){
            $header++;
            $header = $header%$total;
        }
        $array[$header][1] = 1;
        $killed = $array[$header][0];
        $kills++;
        //echo "killed: $killed\n";
        //print_r($array);
    }
    foreach($array as $value2){
        if($value2[1] == 0){
            $survivor = $value2[0]+1;
            $killed++;
            echo str_pad($value[0], 2, ' ', STR_PAD_LEFT).str_pad($value[1], 3, ' ', STR_PAD_LEFT).'    '.str_pad($survivor, 3, ' ', STR_PAD_LEFT).str_pad($killed, 3, ' ', STR_PAD_LEFT)."\n";
        }
    }
}