[백준] 10828번 스택 (파이썬)

10828번: 스택

 

코드

import sys

stack = []
def decision(i):
    if i[0] == 'push':
        stack.append(int(i[1]))
        return
    elif i[0] == 'top':
        if len(stack) >= 1:
            print(stack[-1])
        else:
            print(-1)
    elif i[0] == 'pop':
        if len(stack) >= 1:
            a = stack.pop(-1)
            print(a)
        else:
            print(-1)
    elif i[0] == 'size':
        print(len(stack))
    elif i[0] == 'empty':
        if len(stack) >= 1:
            print(0)
        else:
            print(1)

n = int(input())
comment = list(list(input().split()) for i in range(n))
for i in comment:
    decision(i)