| ps | |
|---|---|
| 링크 | cses.fi/… |
| 출처 | CSES |
| 문제 번호 | 1662 |
| 문제명 | Subarray Divisibility |
| 분류 |
누적합 |
| 시간복잡도 | O(n) |
| 인풋사이즈 | n<=2*10^5 |
| 사용한 언어 | PyPy 3.9 |
| 제출기록 | 0.10s |
| 최고기록 | 0.08s |
| 해결날짜 | 2026/05/07 |
"""Solution code for "CSES 1662. Subarray Divisibility".
- Problem link: https://cses.fi/problemset/task/1662
- Solution link: http://www.teferi.net/ps/problems/cses/1662
"""
import collections
def main():
n = int(input())
a = [int(x) for x in input().split()]
pref_sums = [x := 0] + [x := (x + a_i) % n for a_i in a]
answer = sum(
count * (count - 1) // 2
for count in collections.Counter(pref_sums).values()
)
print(answer)
if __name__ == '__main__':
main()"""Solution code for "CSES 1662. Subarray Divisibility".
- Problem link: https://cses.fi/problemset/task/1662
- Solution link: http://www.teferi.net/ps/problems/cses/1662
"""
def main():
n = int(input())
a = [int(x) for x in input().split()]
count_by_cum_sum = [0] * n
count_by_cum_sum[0] = 1
cum_sum = 0
answer = 0
for x in a:
cum_sum = (cum_sum + x) % n
answer += count_by_cum_sum[cum_sum]
count_by_cum_sum[cum_sum] += 1
print(answer)
if __name__ == '__main__':
main()