## 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 The first line of input contains two integers N and K, the next line contains N space-separated integers depicting values of an array.

Constraints:-

1 < = N < = 100000

1 < = Arr[i] <= 100000

1 <= K <= 100000

Output

Print the count of required pairs.

Example

Sample Input 5 4 1 2 3 4 5

Sample Output 2

Sample Input 5 3 1 2 3 4 5

Sample Output 4

Explanation:- In Sample 2, (1 5), (1 2), (2 4), and (4 5) are the required pairs

## Solution Pair sum divisible by K:–

```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);
}
}```