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from collections import Counter

n = int(input())
seq = [int(x) for x in input().split(' ')]

prefix_sum = [0] * (n + 1)
for i in range(n):
    prefix_sum[i + 1] = prefix_sum[i] + seq[i]

favorite_seq = []
for i in range(n):
    for j in range(i, n):
        favorite_seq.append(prefix_sum[j + 1] - prefix_sum[i])

seq_count = Counter(favorite_seq)
result = 0
for a1, v1 in seq_count.items():
    if a1 == 0:
        result += v1 * (v1 - 1) * (v1 - 2)
    else:
        result += v1 * (v1 - 1) * seq_count[-2 * a1]

    for a2, v2 in seq_count.items():
        if a1 != a2 and - a1 - a2 != a1 and - a1 - a2 != a2:
            result += v1 * v2 * seq_count[-a1 - a2]


print(result // 6)