๋ฐฑ์ค 18258๋ฒ ํ์ด์ฌ
import sys
from collections import deque
# from queue import Queue ๋ชจ๋์ ์ฌ์ฉํ์ฌ๋ ๋จ
input = sys.stdin.readline
n = int(input())
queue = deque([])
for _ in range(n):
method = input().strip()
if method[0:2] == 'pu':
method, val = map(str, method.split())
queue.append(int(val))
else :
if method == 'pop':
if len(queue) > 0:
print(queue.popleft())
else:
print(-1)
elif method == 'size':
print(len(queue))
elif method == 'empty':
if len(queue) > 0:
print(0)
else:
print(1)
elif method == 'front':
if len(queue) > 0:
print(queue[0])
else:
print(-1)
elif method == 'back':
if len(queue) > 0:
print(queue[-1])
else:
print(-1)
list()๋ฅผ ์ฌ์ฉํ์ฌ ํ๋ฅผ ๊ตฌํํ๋ฉด pop(0)์ผ๋ก ์ธํ ์๊ฐ์ด๊ณผ[O(n)]๊ฐ ๋ฐ์ํฉ๋๋ค.
์ด๋ก ์ธํ์ฌ
๊ฐ๋จํ queue๋ฅผ ๊ตฌํํ ๋ collections์ deque๋ queue์ Queue๋ฅผ ์ฌ์ฉํ๋ฉด ๋ฉ๋๋ค.