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<?php function isCorrect($string) { $len = strlen($string); $stack = array(); for( $i = 0; $i < $len; ++$i) { if ( $string[$i] == '(' ) array_push($stack, $string[$i]); elseif( $string[$i] == ')' ) { if ( empty($stack) === false ) array_pop($stack); else return false; } } return empty($stack); } $string = '((()))'; isCorrect($string); //var_dump(isCorrect($string)); //var_dump(strlen($string) % 2); //assert(isCorrect('') === true); //assert(isCorrect('()') === true); //assert(isCorrect('{()}') === true); //assert(isCorrect('{()}{}') === true); //assert(isCorrect('(())') === true); //assert(isCorrect('{({({({()})})})}') === true); //assert(isCorrect('{(})') === false);
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.1 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
Output for 5.1.0
Fatal error: fatal flex scanner internal error--end of buffer missed in /in/0moKK on line 28
Process exited with code 255.

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