<?php

mb_internal_encoding("UTF-8");
function doSquare($n, $m, $a)
{
    $square      = $n * $m;
    $countHeight = ceil($n / $a);
    $countLength = ceil($m / $a);
    $count       = $countHeight * $countLength;
    return $count . "\n";
}
echo doSquare(25, 14, 6);
echo doSquare(8, 8, 7);