Given an array of `N`

integers and an integer `K`

, your task is to calculate the count of pairs whose sum is divisible by `K`

.

### Input Format:

The first line of input contains two integers `N`

and `K`

.

The next line contains `N`

space-separated integers depicting values of an array.

### Output Format:

Print the count of required pairs.

### Example 1

**Input**

5 4 1 2 3 4 5

**Output**

2

**Explanation**

Here , 2 pairs are possible whose sum is divisible by 3 i.e (1 3) and (3 5) are the required pairs

### Example 2

**Input**

5 3 1 2 3 4 5

**Output**

4

**Explanation**

Here , 4 pairs are possible whose sum is divisible by 3 i.e (1 5), (1 2), (2 4), and (4 5) are the required pairs.

### Constraints:

`1 < = N < = 10^5`

`1 < = A[i] <= 10^5`

`1 <= K <= 10^5`

## Solution:–

import java.util.*; import java.lang.*; import java.io.*; public class Main { public static void main (String[] args) throws java.lang.Exception { //your code here Scanner sc = new Scanner(System.in); int N = sc.nextInt(); int K = sc.nextInt(); int arr[] = new int[N]; int count=0; for(int i=0;i<N;i++) { arr[i]=sc.nextInt(); } for(int i=0;i<N;i++) { for(int j=i+1;j<N;j++) { if((arr[i]+arr[j])%K==0) { count++; } } } System.out.println(count); } }

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