Balanced Bracket using Inbuilt Functions.cpp

#include <bits/stdc++.h>

using namespace std;

unordered_map<char, int> symbols = { {'[',-1},{']',1},{'(',-2},{')',2},{'{',-3},{'}',3} };
string bal(string s)
{
    stack<char> st;
    for(char b: s)
    {
        if(symbols[b]<0)
        {
            st.push(b);
        }
        else {
            if(st.empty()) return "NO";
            char top = st.top();
            st.pop();
            if(symbols[top]+ symbols[b] != 0) return "NO";
        }
    }
    if(st.empty()) return "YES";
    else return "NO";
}
int main()
{
    int t; cin>>t;
    while(t--)
    {
        string s;
        cin>>s;
        cout<<bal(s)<<endl;
    }
}