n개의 d차원 음이 아닌 정수 벡터가 주어질 때 내적이 k의 배수가 되는 두 벡터를 찾아 출력하고, 없으면 -1 -1을 출력한다.
어려움8수학조합론완전 탐색정수론아직 제출이 없습니다시간 제한5초메모리 제한512 MBThe inner product (a.k.a. dot product) of two d-dimensional vectors A = [a1, a2, …, ad] and B = [b1, b2, …, bd] is equal to the sum of products of their corresponding components. Given n such d-dimensional vectors, x1, …, xn, Little Meow-Meow would like to know if there exists two vectors whose inner product is a multiple of k. Please help her solve this problem.
The first line of input contains 3 positive integers n, d, and k, respectively representing the number of vectors, the number of dimensions, and the number of which a inner product could be a multiple.
The next n lines each contains d nonnegative integers. On the i-th of these lines, the j-th integer represents xi,j, the j-th component of vector xi.
Output two integers, separated by a space.
If there exists two vectors xp and xq whose inner product is an integer multiple of k, then output their indices p and q (p < q). If there are multiple answers, output any one of them.
If an answer does not exist, then output two -1's separated by a space.
| Test Case | n | d | k | xi,j |
|---|---|---|---|---|
| 1 | 2 | 20 | 2 | ≤ 10 |
| 2 | 5 | 20 | 2 | ≤ 10 |
| 3 | 10 | 20 | 3 | ≤ 10 |
| 4 | 20 | 20 | 2 | ≤ 100 |
| 5 | 50 | 20 | 3 | ≤ 100 |
| 6 | 50 | 50 | 2 | ≤ 1000 |
| 7 | 50 | 50 | 3 | ≤ 3000000 |
| 8 | 80 | 80 | 2 | ≤ 2000000 |
| 9 | 100 | 100 | 3 | ≤ 3000000 |
| 10 | 500 | 100 | 3 | ≤ 3000000 |
| 11 | 1000 | 100 | 2 | ≤ 2000000 |
| 12 | 1000 | 100 | 3 | ≤ 3000000 |
| 13 | 10000 | 100 | 2 | < 10 |
| 14 | 10000 | 100 | 3 | < 10 |
| 15 | 15000 | 100 | 2 | < 10 |
| 16 | 18000 | 100 | 2 | < 10 |
| 17 | 20000 | 100 | 2 | < 10 |
| 18 | 50000 | 30 | 3 | < 10 |
| 19 | 80000 | 30 | 3 | < 10 |
| 20 | 100000 | 30 | 3 | < 10 |