파이썬 백준 10828 : 스택

문제

https://www.acmicpc.net/problem/10828

10828번: 스택

 

 

풀이 

리스트로 stack를 정의하고 입력 명령어에 따라 push, pop, size, empty, top 구현

import sys
N = int(sys.stdin.readline())
stack =[]
for _ in range(N):
    command=sys.stdin.readline()
    if 'push' in command:
        num=int(command.split(' ')[1])
        stack.append(num)
    elif 'pop' in command:
        if len(stack)==0:
            print(-1)
        else:
            print(stack.pop())
    elif 'size' in command:
        print(len(stack))
    elif 'empty' in command:
        print(0 if len(stack) > 0 else 1)
    elif 'top' in command:
        if len(stack)==0:
            print(-1)
        else:
            print(stack[-1])