[baekjoon]python #10828 스택, #10845 큐, #10866 덱

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

10828번: 스택

n=int(input())
arr = []
for i in range(n):
    arr.append(input().split())

stack = []
for i in range(n):
    if arr[i][0] == 'push':
        stack.append(arr[i][1])

    elif arr[i][0] == 'size':
        print(len(stack))

    elif arr[i][0] == 'empty':
        if len(stack) == 0:
            print(1)
        else:
            print(0)

    elif arr[i][0] == 'pop':
        if len(stack) == 0:
            print(-1)
        else:
            print(stack.pop(len(stack)-1))

    elif arr[i][0] == 'top':
        if len(stack) == 0:
            print(-1)
        else:
            print(stack[-1])

https://www.acmicpc.net/problem/10845

10845번: 큐

n=int(input())
arr = []
for i in range(n):
    arr.append(input().split())

queue = []
for i in range(n):
    if arr[i][0] == 'push':
        queue.append(arr[i][1])

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

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

    elif arr[i][0] == 'size':
        print(len(queue))

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

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

https://www.acmicpc.net/problem/10866

10866번: 덱

from collections import deque
import sys
n= int(sys.stdin.readline())
arr = []
for i in range(n):
    arr.append(sys.stdin.readline().split())

queue = deque()
for i in range(n):
    if arr[i][0] == 'push_front':
        queue.appendleft(arr[i][1])

    elif arr[i][0] == 'push_back':
        queue.append(arr[i][1])

    elif arr[i][0] == 'pop_front':
        if len(queue) == 0:
            print(-1)
        else:
            print(queue.popleft())

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

    elif arr[i][0] == 'size':
        print(len(queue))

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

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

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

2022.05.31 - [Problem Solving/ALGORITHM] - deque

deque