<?php

function comp($a = [], $b = []): bool {
  // Protect against degenerate cases using invalid arguments.
  if (gettype($a) !== gettype($b) || count($a) != count($b)) {
    return false;
  }
  sort($a);
  sort($b);
  for ($i = 0; $i < count($a); $i++) {
    $x = $a[$i]*$a[$i];
    if ($x != $b[$i]) {
      return false;
    }
  }
  return true;
}