# [Solution] Count Array Pairs Divisible by K solution leetcode

Count Array Pairs Divisible by K solution leetcode – Given a 0-indexed integer array `nums` of length `n` and an integer `k`, return the number of pairs `(i, j)` such that:

• `0 <= i < j <= n - 1` and
• `nums[i] * nums[j]` is divisible by `k`.

# Count Array Pairs Divisible by K solution leetcode

```Input: nums = [1,2,3,4,5], k = 2
Output: 7
Explanation:
The 7 pairs of indices whose corresponding products are divisible by 2 are
(0, 1), (0, 3), (1, 2), (1, 3), (1, 4), (2, 3), and (3, 4).
Their products are 2, 4, 6, 8, 10, 12, and 20 respectively.
Other pairs such as (0, 2) and (2, 4) have products 3 and 15 respectively, which are not divisible by 2.
```

## Count Array Pairs Divisible by K solution leetcode

```Input: nums = [1,2,3,4], k = 5
Output: 0
Explanation: There does not exist any pair of indices whose corresponding product is divisible by 5.
```

Constraints:

• `1 <= nums.length <= 105`
• `1 <= nums[i], k <= 105`