[Python] 백준 #18258. 큐 2

https://www.acmicpc.net/problem/18258

18258번: 큐 2

 

# 18258 - Python 3

import sys
from collections import deque

input = sys.stdin.readline

n = int(input())

arr = []

s = deque()

for i in range(n):
    arr = input().split()

    if "push" in arr[0:4]:
        s.append(arr[-1])
    elif "pop" in arr[0:3]:
        if s:
            a = s.popleft()
            print(a)
        else:
            print("-1")
    elif "size" in arr[0:4]:
        print(len(s))
    elif "empty" in arr[0:5]:
        if s:
            print("0")
        else:
            print("1")
    elif "front" in arr[0:5]:
        if s:
            print(s[0])
        else:
            print("-1")
    elif "back" in arr[0:4]:
        if s:
            print(s[-1])
        else:
            print("-1")