백준 10866 - 덱 (파이썬)

Answer

from collections import deque
import sys

input = sys.stdin.readline

d = deque([])
for _ in range(int(input())):
    a = input().split()
    if a[0] == 'push_front':
        d.appendleft(int(a[1]))
    elif a[0] == 'push_back':
        d.append(int(a[1]))
    elif a[0] == 'pop_front':
        if d:
            print(d.popleft())
        else:
            print(-1)
    elif a[0] == 'pop_back':
        if d:
            print(d.pop())
        else:
            print(-1)
    elif a[0] == 'size':
        print(len(d))
    elif a[0] == 'empty':
        if d:
            print(0)
        else:
            print(1)
    elif a[0] == 'front':
        if d:
            print(d[0])
        else:
            print(-1)
    elif a[0] == 'back':
        if d:
            print(d[-1])
        else:
            print(-1)