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<?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);

This is an error 500

Value for `_results` contains invalid data `array`


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