[심심풀이 백준문제풀기] 1874번 스택 수열 (파이썬3)

문제 : https://www.acmicpc.net/problem/1874

r = int(input())
stack =[]
chk = []
result = []
# 기본 세팅
for i in range(r) :
    chk.append(int(input()))
idx = 0
for i in range(1,r+1) :
    stack.append(i)
    result.append("+")

    while idx < r and  len(stack) != 0 and chk[idx] == stack[-1] :
        stack.pop()
        result.append("-")
        idx = idx + 1

if not stack :
    for i in result :
        print(i)
else :
    print("NO")