In this Divisible Sum Pairs problem you have Given an array of integers and a positive integer k, determine the number of (i,j) pairs where i < j and ar[i]+ar[j] is divisible by k.

HackerRank Divisible Sum Pairs problem solution


Problem solution in Python programming.

#!/bin/python3

import sys


n,k = input().strip().split(' ')
n,k = [int(n),int(k)]
a = [int(a_temp) for a_temp in input().strip().split(' ')]
acc = 0
for i, e in enumerate(a):
    for j in range(i+1, len(a)):
        acc += (e + a[j]) % k == 0
print(acc)


Problem solution in Java Programming.

import java.io.*;
import java.util.*;
import java.text.*;
import java.math.*;
import java.util.regex.*;

public class Solution {

    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int n = in.nextInt();
        int k = in.nextInt();
        int a[] = new int[n];
        for(int a_i=0; a_i < n; a_i++){
            a[a_i] = in.nextInt();
        }
        int cnt=0;
        for (int i = 0 ;i<n-1;i++) {
            for (int j=i+1;j<n;j++) {
                if ((a[i]+a[j]) % k == 0)
                    cnt ++;
            }
        }
        System.out.println(cnt);
    }
}


Problem solution in C++ programming.

#include <map>
#include <set>
#include <list>
#include <cmath>
#include <ctime>
#include <deque>
#include <queue>
#include <stack>
#include <string>
#include <bitset>
#include <cstdio>
#include <limits>
#include <vector>
#include <climits>
#include <cstring>
#include <cstdlib>
#include <fstream>
#include <numeric>
#include <sstream>
#include <iostream>
#include <algorithm>
#include <unordered_map>

using namespace std;


int main(){
    int n;
    int k;
    int count = 0;
    cin >> n >> k;
    vector<int> a(n);
    for(int a_i = 0;a_i < n;a_i++){
       cin >> a[a_i];
    }
    
    for(int i =0 ; i < n -1 ; i++){
        for(int j=i+1 ; j < n ; j++){
            if( (a[i]+a[j])%k ==0){
                count++;
            }
        }
    }
    
    cout << count;
    return 0;
}


Problem solution in C programming.

#include <math.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <assert.h>
#include <limits.h>
#include <stdbool.h>

int main(){
    int n; 
    int k; 
    scanf("%d %d",&n,&k);
    int *a = malloc(sizeof(int) * n);
    for(int a_i = 0; a_i < n; a_i++){
       scanf("%d",&a[a_i]);
    }
    
    int sum = 0;
    for (int i = 0; i < n; i++) {
        for (int j = i+1; j < n; j++) {
            if ( (a[i]+a[j])%k == 0)
                sum++;
        }
    }
    
    printf("%d\n",sum);
    
    return 0;
}


Problem solution in JavaScript programming.

process.stdin.resume();
process.stdin.setEncoding('ascii');

var input_stdin = "";
var input_stdin_array = "";
var input_currentline = 0;

process.stdin.on('data', function (data) {
    input_stdin += data;
});

process.stdin.on('end', function () {
    input_stdin_array = input_stdin.split("\n");
    main();    
});

function readLine() {
    return input_stdin_array[input_currentline++];
}

/////////////// ignore above this line ////////////////////

function main() {
    var n_temp = readLine().split(' ');
    var n = parseInt(n_temp[0]);
    var k = parseInt(n_temp[1]);
    a = readLine().split(' ');
    a = a.map(Number);
    
    count = 0;

    for(i = 0; i < n; i++)
    {
        for(j = 0; j < n; j++)
        {
            if((i < j) && (((a[i] + a[j]) % k) == 0))
            {
                count++;
            }
        }    
     
    }
    
    console.log(count);

}