<?php

error_reporting(-1);

$creditBalance = 40000;
$percent = 1.03;
$servicePayment = 1000;
$monthlyPayment = 5000;
$paymentTotal = 0;

for ($month = 1; $month <= 20; $month ++) {
	
	$creditBalance = ( $creditBalance * $percent ) + $servicePayment - $monthlyPayment;
	$paymentTotal = $paymentTotal + $monthlyPayment;
	echo "{$month} месяц спустя: долг = {$creditBalance} руб, выплачено всего {$paymentTotal} руб. \n";

      if ($creditBalance < 0) {
          echo "С меня хватит!\n";
          break;
      }
        elseif ($creditBalance == 0) {
      	  echo "NAKANECTA!!";
      	  break;
      }
      elseif ($creditBalance < $monthlyPayment) {
      	  $lastPayment = $monthlyPayment - $creditBalance;
      	  $monthlyPayment = ($monthlyPayment - abs($lastPayment)) * $percent + $servicePayment;
      }
    
}
?>