UNSW ProgComp: Problem 5 - 2007

<?php

$input = <<<END
31
-3 4 23 6 -5 6 -124 -2 4 0 16 -3 0 -6 15 9 -3 -4 -1 6 0 -3 2 -2 2 -2 -2 2 2 2 -2
END;

//scrap the first line and turn the second line into an array
$input = explode("\n", $input);
array_shift($input);
$input = explode(" ", $input[0]);
//this is just going to have to be a brute force, sorry guys

//one loop for length
//another loop for position start
$max_sum = array(null, null, null); //sum, start, length

for($x = 1; $x < count($input); $x++){
    //this loop is for length
    for($y = 0; $y < count($input)-$x; $y++){
        //this loop is for start position
        $sum = 0;
        for($z = $y; $z < $y+$x; $z++){
            //this loop is for accumulation
            $sum += $input[$z];
        }
        if($sum > $max_sum[0]){
            $max_sum[0] = $sum;
            $max_sum[1] = $y;
            $max_sum[2] = $x;
        }
    }
}

for($x = $max_sum[1]; $x < $max_sum[1]+$max_sum[2]; $x++){
    if($x == $max_sum[1]){
        echo $input[$x];
    }else{
        echo ' + '.$input[$x];
    }
}
echo ' = '.$max_sum[0];