<?php
$charset = "abcdefghijklmnopqrstuvwxyz0123456789";
$charset_len = strlen($charset);
$current_len = 4;
$password = str_repeat(' ', $current_len);
$state = array_fill(0, $current_len, 0);
 
while (true)
{
  $carry = true;
 
  // Генерируем пароль и сразу же следующее состояние.
 
  for ($i = 0; $i < $current_len; ++$i) {
    $password[$i] = $charset[$state[$i]];
 
    if ($carry) {
      if (++$state[$i] !== $charset_len) {
        $carry = false;
      } else {
        $state[$i] = 0;
      }
    }
  }
 
  if ($carry) {
    echo "No luck!\n";
    break;
  }
 
  if (md5($password) == "e7806b130b429fc9b5890608a2c60675") {
    echo "YES!\n\nPassword is '$password'\n";
    break;
  }
}
?>
 

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