<?php
function countCredit($creditSum, $payout, $creditPercent, $commision, $openPay) {
    $month = 0;
    $totalPay = 0;
    $creditSum = (($creditSum * $creditPercent) + $commision) + $openPay;
    for ($creditSum; $creditSum < 0; $creditSum - $payout) {
        $creditSum = (($creditSum * $creditPercent) + $commision);
        $month++;
        $totalPay = $totalPay + $payout;
        echo "Прошел $month месяц, выплачено $totalPay, осталось заплатить $creditSum";
    }
}
 
$homeCreditTotal = countCredit(39999, 5000, 1.04, 500, 0);
$softbankTotal = countCredit(39999, 5000, 1.03, 1000, 0);
$strawberryBankTotal = countCredit(39999, 5000, 1, 0, 7777);
 
echo "$homeCreditTotal<br/>";
echo "$softbankTotal<br/>";
echo "$strawberryBankTotal<br/>";
?>

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