Как не потерять почту когда умирают ДЦ или о надежности DNS

function plural($num, $data)
{
  //This would make a word plural according to $num, currently works for russian & english
  //Second parameter is $data['lang'][$language_form]
  if(lang()=='en')
  {
    //For english only 2 forms, 0 and 1.
    // x0 - days form 1
    // x1 - day form 0
    // x2 - days form 1
    return $data['en'][($num>1 || $num==0)];
  } else
  if(lang()=='ru')
  {
    //For russian: (день)
    // x0 - дней | form 0
    // x1 - день | form 1
    // x2 - дня | form 2
    // x3 - дня | form 2
    // x4 - дня | form 2
    // x5 - дней | form 0
    // x6 - дней | form 0
    // x7 - дней | form 0
    // x8 - дней | form 0
    // x9 - дней | form 0
    if($num>9 && $num<20)//exception for 10-19
          return $data['ru'][0];
    
    switch ($num%10)
    {
      case 1:
          return $data['ru'][1];
      case 2:
      case 3:
      case 4:
          return $data['ru'][2];
      default:
          return $data['ru'][0];
    }
  } else
    return 'unknown';
}

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