<?php
 
function bestBankCalculator($percent, $commission, $creditSum, $payout, $downPayment){
	$creditSum += $downPayment;
	while($creditSum > 0){
		$creditSum = ($creditSum * $percent + $commission);
		if($creditSum > $payout){
			$creditSum -= $payout;
			$totalPaid += $payout; 
		}
		else{
			$creditSum -= $creditSum;
			$totalPaid += $creditSum;
		}
	}
	return $totalPaid;
}
 
$homoCreditTotal = bestBankCalculator(1.04, 500, 39999, 5000, 0);
$softbankTotal = bestBankCalculator(1.03, 1000, 39999, 5000, 0);
$strawberryBankTotal = bestBankCalculator(1.02, 0, 39999, 5000, 7777);
 
echo "homoCredit: {$homoCreditTotal} руб.\n";
echo "softbank: {$softbankTotal} руб. \n";
echo "strawberryBank: {$strawberryBankTotal} руб. \n";