201403-1 CCF认证考试 相反数 Python版

满分答案：

import copy
n = int(input())
no = list(map(int,input().split()))
no_1 = copy.deepcopy(no)
count = 0
for i in range(n):
    if -no[i] in no_1:
        count = count + 1
    no_1.remove(no[i])
print(count)