<?php

function execute_code($opnr, $a, $b, $c)
{
    global $register;

    switch ($opnr)
    {
        case 'addr':
            $register[$c] = $register[$a] + $register[$b];
            break;
        case 'addi':
            $register[$c] = $register[$a] + $b;
            break;
        case 'mulr':
            $register[$c] = $register[$a] * $register[$b];
            break;
        case 'muli':
            $register[$c] = $register[$a] * $b;
            break;
        case 'banr':
            $register[$c] = $register[$a] & $register[$b];
            break;
        case 'bani':
            $register[$c] = $register[$a] & $b;
            break;
        case 'borr':
            $register[$c] = $register[$a] | $register[$b];
            break;
        case 'bori':
            $register[$c] = $register[$a] | $b;
            break;
        case 'setr':
            $register[$c] = $register[$a];
            break;
        case 'seti':
            $register[$c] = $a;
            break;
        case 'gtir':
            $register[$c] = $a > $register[$b] ?1:0;
            break;
        case 'gtri':
            $register[$c] = $register[$a] > $b ?1:0;
            break;
        case 'gtrr':
            $register[$c] = $register[$a] > $register[$b] ?1:0;
            break;
        case 'eqir':
            $register[$c] = $a === $register[$b] ?1:0;
            break;
        case 'eqri':
            $register[$c] = $register[$a] === $b ?1:0;
            break;
        case 'eqrr':
            $register[$c] = $register[$a] === $register[$b] ?1:0;
            break;
        default:
            printf('Op code not found: %s', $opnr);
            exit();

    }
}

$input = file("input.txt");

$pointer = (int)explode(' ', trim(array_shift($input)))[1];

$codes = array();

foreach ($input as $line)
{
    $code = explode(' ', trim($line));
    $code[1] = (int)$code[1];
    $code[2] = (int)$code[2];
    $code[3] = (int)$code[3];
    $codes[] = $code;
}

$register = array(0,0,0,0,0,0);
$exec = $register[$pointer];

while($exec < count($input))
{

    $register[$pointer] = $exec;

    $code = $codes[$exec];

    execute_code($code[0], $code[1], $code[2], $code[3]);

    $exec = $register[$pointer];
    $exec++;
}
printf('Part 1: %d', $register[0]);
echo PHP_EOL;

$register = array(1,0,0,0,0,0);
$exec = $register[$pointer];

while($exec < count($input))
{

    $register[$pointer] = $exec;

    $code = $codes[$exec];

    execute_code($code[0], $code[1], $code[2], $code[3]);

    $exec = $register[$pointer];
    $exec++;
    if($exec === 2 && $register[1] !== 0) {
        $register[5] = 0;
        $register[3] = $register[2];

        if($register[2] % $register[1] === 0) {
            $register[0] += $register[1];
        }

        $exec = 12;

    }
}
printf('Part 2: %d', $register[0]);
echo PHP_EOL;