Divisible Sum Pairs

 

Given an array of integers and a positive integer , determine the number of  pairs where  and  +  is divisible by .

Example

Three pairs meet the criteria:  and .

Function Description

Complete the divisibleSumPairs function in the editor below.

divisibleSumPairs has the following parameter(s):

• int n: the length of array 
• int ar[n]: an array of integers
• int k: the integer divisor

Returns
- int: the number of pairs

Input Format

The first line contains  space-separated integers,  and .
The second line contains  space-separated integers, each a value of .

Constraints

Sample Input

STDIN           Function
-----           --------
6 3             n = 6, k = 3
1 3 2 6 1 2     ar = [1, 3, 2, 6, 1, 2]

Sample Output

 5

Explanation

Here are the  valid pairs when :

Program:

#!/bin/python3

import math

import os

import random

import re

import sys

# Complete the divisibleSumPairs function below.

def divisibleSumPairs(n, k, ar):

    count=0

    for i in range(0,n-1):

        for j in range(i+1,n):

            if (ar[i]+ar[j])%k == 0:

                count+=1

    return count

if __name__ == '__main__':

    fptr = open(os.environ['OUTPUT_PATH'], 'w')

    nk = input().split()

    n = int(nk[0])

    k = int(nk[1])

    ar = list(map(int, input().rstrip().split()))

    result = divisibleSumPairs(n, k, ar)

    fptr.write(str(result) + '\n')

    fptr.close()

Output:

Compiler Message

Success

Input (stdin)

• 6 3

• 1 3 2 6 1 2

Expected Output

• 5