[알고리즘] 큐 백준 10845 (Python)

queue 는 선입선출이라는 것을 기억하고 풀었다.

 

코드

import sys

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

queue = []

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

  if command[0] == 'push' :
    queue.insert(0,command[1])

  elif command[0] == 'pop' :
    if len(queue) == 0:
      print(-1)
    else :
      print(queue.pop())

  elif command[0] == 'size' :
    print(len(queue))
  
  elif command[0] == 'empty' :
    if len(queue) == 0 :
      print(1)
    else :
      print(0)

  elif command[0] == 'front' :
    if len(queue) == 0 :
      print(-1)
    else :
      print(queue[-1])

  elif command[0] == 'back' :
    if len(queue) == 0 :
      print(-1)
    else :
      print(queue[0])

 

입출력