c_cpp 20.有效括号 - 简单 - 2018/11/13

Posted 2021-05-14

class Solution {
public:
    bool isValid(string s) {
        stack<char> st;
        for (char c : s) {
            if (st.empty()) {
                st.push(c);
                continue;
            }
            
            char topC = st.top();
            if ((c == ')' && topC == '(')
                || (c == ']' && topC == '[')
                || (c == '}' && topC == '{')) {
                st.pop();
                continue;
            }
            
            st.push(c);
        }
        return st.empty();
    }
};