File Status: Solution File found. Code from the function code_solution_4 will be used

Solution: 993 * 913 = 906609

Solution Code:

      <?php

  function code_solution_4() {
    $palindromes = [];
    $answer = 0;
    $largest_value = 999*999; // 998001
    $largest_i = null;
    $largest_j = null;

    $i = 999;
    $j = 999;
    $iterations = 3000;

    for($i = 999; $i > 99; $i--) {
      for($j = 999; $j > 99; $j--) {
        $product = $i*$j;
        if(is_palindrome($product)) {
          $palindromes[] = $product;
          if($product > $answer) {
            $answer = $product;
            $largest_i = $i;
            $largest_j = $j;
          }
        }
      }
    }

    return "{$largest_i} * {$largest_j} = {$answer}";

    //return implode(', ', $palindromes);
  }