n = int(input())
numbers = list(map(int, input().split()))

pref_sums = [0]
pref_sums_indexes = {0: 0}

interesting_left_to_right = {}

for index, number in enumerate(numbers):
    pref_sums.append(pref_sums[-1] + number)
    if pref_sums[-1] in pref_sums_indexes:
        left_index = pref_sums_indexes[pref_sums[-1]]
        interesting_left_to_right[left_index] = index
    pref_sums_indexes[pref_sums[-1]] = index + 1


good_amount = 0
current_good_left = 0
for left in range(n):
    while current_good_left < n and (current_good_left < left or current_good_left not in interesting_left_to_right):
        current_good_left += 1
    if current_good_left < n:
        good_amount += n - interesting_left_to_right[current_good_left]

print(good_amount)