deque

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

signed main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
        /*
    deque<int> q;
    q.size(); // olcusu
    q.empty(); // bos olarsa true

    q.back(); // sagdaki
    q.push_back(x); // sagdan elave
    q.pop_back(); // sagdakini sil

    q.front(); // soldaki
    q.push_front(x); // sola elave
    q.pop_front(); // soldakini sil
    */
    /*
    deque<int> q;
    q.push_back(7);
    q.push_front(5);
    for(int i = 0; i < q.size(); i++){
        cout << q[i] << " ";
    }
*/
}