力ボタン-スタックを使用して有効なカッコかどうかを判断します.

require 'Stack.php';
class Solution {

    protected static $solution = [
        '(' => ')',
        '{' => '}',
        '[' => ']'
    ];
    /**
     *       
     * https://leetcode-cn.com/problems/valid-parentheses/
     *           
     * @param String $s
     * @return Boolean
     */
    public function isValid($s) {
        $stack = new Stack();
        $len = strlen($s);
        for($i=0;$ipush($char);
            }else{
                if($stack->isEmpty()) return false;
                $left = $stack->pop();
                if($char !== self::$solution[$left]) return false;
            }
        }
        return $stack->isEmpty();
    }
}


$solution = new Solution();
$ret = $solution->isValid('([{]}])');
var_dump($ret);