Shared code

"""
https://cses.fi/problemset/task/1662
5
3 1 2 7 4 should output 1
"""
divisor = int(input())
remainders_encountered = {}
sum_so_far = 0
for i in input().split():
    sum_so_far += int(i)
    remainder = sum_so_far % divisor
    if remainder not in remainders_encountered:
        remainders_encountered[remainder] = 0
    remainders_encountered[remainder] += 1

total = 0
for r, i in remainders_encountered.items():
    if r == 0:
        total += i * (i + 1) // 2
    else:
        total += i * (i - 1) // 2
print(total)