백준 1927. 최소 힙

https://www.acmicpc.net/problem/1927

import heapq, sys
input = sys.stdin.readline

n = int(input())
heap = []
for _ in range(n):
    x = int(input())
    if x == 0:
        print(heapq.heappop(heap)) if heap else print(0)
    else:
        heapq.heappush(heap, x)