要一遍做对——LeetCode题目20：有效的括号

class Solution {
public:
    bool isValid(string s) {
        map<char, char> table = {
            {')', '('}, {']','['}, {'}','{'}
        };

        stack<char> my_stack;
        for (int i = 0; i < s.size(); ++i) {
            if (s[i] == '(' || s[i] == '[' || s[i] == '{') {
                my_stack.push(s[i]);
            } else if (s[i] == ')' || s[i] == ']' || s[i] == '}') {
                if (my_stack.size() == 0 || table[s[i]] != my_stack.top()) return false;
                else my_stack.pop();
            }
        }

        bool suc = my_stack.size() == 0 ? true: false;
        return suc;
    }
};