Given an array of integers and a positive integer k, determine the number of (i,j) pairs in the array where i<j and arr[i] + arr[j] is divisible by k.

### Example

arr = [1, 2, 3, 4, 5, 6] k = 5 Three pairs meet the criteria: [1, 4], [2, 3] and [4, 6].

### Input Format

The first line contains 2 space-separated integers, n and k.

The second line contains n space-separated integers, each a value of arr[i].

### Sample Input

6 3 1 3 2 6 1 2

#### Sample Output

5

#### Explanation

Here are the 5 valid pairs when k = 3:

(0,2) = arr[0]+arr[2] = 1 + 2 = 3

(0,5) = arr[0]+arr[5] = 1+ 2 = 3

(1,3) = arr[1]+arr[3] = 3 + 6 = 9

(2,4) = arr[2]+arr[4] = 2 + 1 = 3

(4,5) = arr[4]+arr[5] = 1 + 2 = 3

## Solution of Divisible Sum Pairs in java:–

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 scanner = new Scanner(System.in); int n = scanner.nextInt(); int k = scanner.nextInt(); int arr[] = new int[n]; int count=0; for(int i=0;i<n;i++) { int value =scanner.nextInt(); arr[i]=value; } for(int i=0;i<n;i++) { for(int j=0;j<n;j++) { if((arr[i]+arr[j])%k==0 && i<j) { count++; } } } System.out.println(count); } }

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