<?php

error_reporting(-1);

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

for ($month = 1; $month <= 13; $month ++) {
    $fullPayment =  ( $creditBalance * $percent ) + $servicePayment;
    if ($fullPayment<$monthlyPayment) {
        $monthlyPayment=$fullPayment;
    }
	$creditBalance =  $fullPayment - $monthlyPayment;
	$paymentTotal = $paymentTotal + $monthlyPayment;
    echo "{$month} месяц спустя: долг = {$creditBalance} руб, выплачено всего {$paymentTotal} руб. \n";
    
   if ($creditBalance == 0) {
          echo "Выплачено, блжад!\n";
          break;
      }
}