有效的括号

[pwstrick]

20.有效的括号

/**
 * @param {string} s
 * @return {boolean}
 */
var isValid = function(s) {
    const length = s.length; 
    let i = 0, j = 0;
    const stack = [];
    while(i < length) {
        let stackLen = stack.length > 0 ? stack.length - 1 : stack.length;
        if((stack[stackLen] == '(' && s[i] == ')') ||
            (stack[stackLen] == '{' && s[i] == '}') ||
            (stack[stackLen] == '[' && s[i] == ']')) {
            stack.pop();
            i++;
            continue;
        }
        stack.push(s[i]);
        i++;
    }
    //console.log(stack)
    return stack.length === 0;
};