#include <vector>
class Parenthesis {
  public:
    bool chkParenthesis(string A, int n) {
        // write code here
        vector<char> stk;
        for (auto c : A) {
            if (c == '(') {
                stk.push_back(c);
                continue;
            }
            if(c ==')')
            {
                if(stk.empty()) return false;
                stk.pop_back();
            }
        }
        return stk.empty();
    }
};