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 { //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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