skobki

#include <bits/stdc++.h>
using namespace std;

int main(){

    int n;
    string s;
    cin >> n >> s;

    bool flag = true;
    vector<char> stack(0);
    for(auto ch: s){
        if(ch == '(' || ch == '[')
            stack.push_back(ch);
        else{
            if(stack.empty()){
                flag = false;
                break;
            }
            if(ch == ']' && stack.front() == '[' || ch == ')' && stack.front() == '('){
                stack.pop_back();
            }else{
                flag = false;
                break;
            }
        }
    }

    if(flag)
        cout << "YES";
    else
        cout << "NO";

}