## Pair sum divisible by K in java

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
{
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);
}
}```