백준. 10845번. 파이썬 풀이
문제링크 https://www.acmicpc.net/problem/10845
import sys
input = sys.stdin.readline
from collections import deque
n = int(input())
q = deque()
for _ in range(n):
command = input().split()
if "push" == command[0]:
q.append(command[1])
elif "front" == command[0]:
if q:
print(q[0])
else:
print(-1)
elif "back" == command[0]:
if q:
print(q[-1])
else:
print(-1)
elif "empty" == command[0]:
if q:
print(0)
else:
print(1)
elif "pop" == command[0]:
if q:
print(q.popleft())
else:
print(-1)
elif "size" == command[0]:
print(len(q))