How to loop through an array separated by commas?

Question

PHP

How to loop through an array separated by commas, and put a dot after the last element?
There is an associative array $tags,

Array ( [0] => Адин [1] => Два[2] => Три [3] => Четыре[4] => Пять)

Code for iterating an array.

foreach ($tags as $tgs) {
  echo $tgs;
}

There was an idea with counting the number of elements in an array, but the code is too complicated. Are there vanilla tags for this case?

Answer 1

Krch, did not understand anything from what was written. I threw a simple script here with crutches.

$cnt = count($string2);
$i = 0;
while ($i < $cnt-1)
{
    echo $string2[$i].", ";
    $i++;
}
echo (end($string2)).".";

Answer 2

$str = implode(',', $array) . '.';