[BOJ] 18115번 카드 놓기

#include <bits/stdc++.h>
#define FASTIO ios::sync_with_stdio(0), cin.tie(0), cout.tie(0)
using namespace std;

const int MAX = 1000005;
int arr[MAX];

int main(){
    FASTIO;
    
    deque<int> dq;
    int n; cin >> n;
    for (int i = 0; i < n; i++) dq.push_back(i);
    
    for (int i = n; i > 0; i--){
        int num; cin >> num;
        if (num == 1) {
            int idx = dq.front();
            dq.pop_front();
            arr[idx] = i;
        }
        else if (num == 2){
            int idx = dq.front();
            dq.pop_front();
            int idx2 = dq.front();
            dq.pop_front();
            dq.push_front(idx);
            arr[idx2] = i;
        }
        else{
            int idx = dq.back();
            dq.pop_back();
            arr[idx] = i;
        }
    }
    
    for (int i = 0; i < n; i++) cout << arr[i] << ' ';
    return 0;
}

 

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