<?php $str ="it is a test string."; $y="r"; $x="m"; $len=strlen($str); if($str[0]==$y) { $str=substr_replace($str,$x,0,1); } if($len>=3) { for($i=3;$i<$len;$i+=4) { if($str[$i]==$y) { $str=substr_replace($str,$x,$i,1); } } } var_dump($str);
You have javascript disabled. You will not be able to edit any code.