白駿10845:Q

10845キュー

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C++コード

#include <iostream>
#include <queue>
#include <string>

using namespace std;

int main() {
 
    int N;
    cin >> N;
    
    queue<int> Q;
    
    while(N--) {
        string M;
        cin >> M;
        
        if(M == "push") {
            int dt;
            cin >> dt;
            Q.push(dt);
        }
        else if(M == "pop") {
            if(Q.empty()) {
                cout << -1 << endl;
            }
            else {
                cout << Q.front() << endl;
                Q.pop();
            }
        }
        else if(M == "size") {
            cout << Q.size() << endl;
        }
        else if(M == "empty") {
            cout << Q.empty() << endl;
        }
        else if(M == "front") {
            if(Q.empty()) {
                cout << -1 << endl;
            }
            else {
                cout << Q.front() << endl;
            }
           
        }
        else if(M == "back") {
            if(Q.empty()) {
                cout << -1 << endl;
            }
            else {
                cout << Q.back() << endl;
            }
        }
    }
    return 0;
}

Pythonコード

import sys

Q = []

N = int(sys.stdin.readline())

for i in range(N):
    command = sys.stdin.readline().split()

    if command[0] == "push":
        dt = command[1]
        Q.append(dt)
    elif command[0] == "pop":
        if len(Q) == 0:
            print(-1)
        else:
            print(Q.pop(0))
    elif command[0] == "size":
        print(len(Q))
    elif command[0] == "empty":
        if len(Q) == 0:
            print(1)
        else:
            print(0)
    elif command[0] == "front":
        if len(Q) == 0:
            print(-1)
        else:
            print(Q[0])
    elif command[0] == "back":
        if len(Q) == 0:
            print(-1)
        else:
            print(Q[-1])