[Baekjoon] 백준 1253 좋다 Python

https://www.acmicpc.net/problem/1253

 

cnt = 0

N = int(input())
num = list(map(int, input().split(" ")))
num.sort()
cnt = 0

for i in range(N):
    target = num[i]

    left = 0
    right = N-1

    while left < right:

        if left == i:
            left += 1
            continue

        if right == i:
            right -= 1
            continue

        total = num[left] + num[right]

        if total == target:
            cnt += 1
            break
        elif total < target:
            left += 1
        else:
            right -= 1

print(cnt)