function solve($discs) {
for ($i = 0;;$i++) {
foreach ($discs as $disc) if (Math::mod($disc[0] + $i, $disc[1])) continue 2;
return $i;
}
}
$discs = $input->lines->map(function ($line) {
$nums = $line->numbers();
return [Math::mod($nums[3] + $nums[0], $nums[1]), $nums[1]];
});
// ==================================================
// > SOLUTIONS
// ==================================================
$solution_1 = solve($discs);
$discs[] = [Math::mod(0 + count($discs) + 1, 11), 11];
$solution_2 = solve($discs);