3v4l.org

run code in 300+ PHP versions simultaneously
<?php function isCorrect($string) { $string{strlen($string)-1}; } assert(isCorrect('') === true); assert(isCorrect('()') === true); assert(isCorrect('{()}') === true); assert(isCorrect('{()}{}') === true); assert(isCorrect('(())') === true); assert(isCorrect('{({({({()})})})}') === true); assert(isCorrect('{(})') === false);

preferences:
55.05 ms | 402 KiB | 5 Q