[PHPID QUIZ] Segitiga

gistfile1.txt

<?php

$a = '.';
$space = ' ';
$ulang = 20;

for ($i = 1; $i < $ulang; $i+= 2) {
    for ($j = ($ulang-$i)/2; $j >= 0; $j--) {
        echo $space;
    }

    for ($k = 0; $k < $i; $k++) {
        echo $a;
    }
    echo PHP_EOL;
}

for ($l = 1; $l < $ulang; $l += 2) {
    for ($m = 0; $m < $l/2; $m++) {
        echo $space;
    }
    for ($n = ($ulang - $l); $n > 0; $n--) {
        echo $a;
    }
    echo PHP_EOL;
}