Online PHP editor | output for 4kM9W

<?php $string = "[vc_tab [vc_tab [vc_tab [vc_tab [vc_tab [vc_tab"; $active = 3; $needle = "[vc_tab"; $replace = '[vc_tab active="true"'; if( substr_count( $string, $needle) < $active) { throw new Exception("There aren't enough needles in the string to do this replacement"); } $count = 0; $index = 0; while( $count++ < $active) { $index = strpos( $string, $needle, $index) + ; } $result = substr( $string, $index - strlen( $needle)) . $replace . substr( $string, $index); echo "Index: ", $index, " ", $result;