<?php
 
error_reporting(-1);
 
$credit = 1000;
$percent = 0.03;
$commission = 1000;
$payment = 5000;
 
$rate = 1 + $percent;
 
do {
    $credit = $credit * $rate + $commission;
    $log .= "Current month sum: $credit \n";
 
    $credit -= $payment;
    $log .= "Sum, after anon paid: $credit \n";
 
    $period++;
    $log .= "Current month $period\n\n";
 
} while (($credit * $rate + $commission) > $payment);
 
$credit = $credit * $rate + $commission;
 
$log .= "Current month sum: $credit \n";
 
$sum = $period * $payment + $credit;
$credit = 0;
$period++;
 
$log .= "Sum, after anon paid: $credit\n"."Current month $period\n\n";
 
echo "Anon paid for $period month. \n Whole sum: $sum.\n Credit: $credit \n\n";
echo $log;

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