https://school.programmers.co.kr/learn/courses/30/lessons/42584
def solution(prices):
answer = []
for i, price in enumerate(prices):
for j, k in enumerate(range(i, len(prices))):
if price > prices[k] or k+1==len(prices): # 이전 값보다 작을 때 or 마지막까지 갔을 때
answer.append(j)
break
return answer