Count all sub-arrays having sum divisible by k

Given an array ‘ARR’ and an integer ‘K’, your task is to find all the count of all sub-arrays whose sum is divisible by the given integer ‘K’.

Note:
If there exists no subarray in the given sequence whose sum is divisible by ‘K’ then simply return ‘0’.
Example:
Suppose the given array is ‘ARR’ = { 5, 0, 2, 3, 1} and ‘K = 5’.
As we can see in below image, there are a total of 6 subarrays that have the total sum divisible by ‘K’
So we return the integer 6.

subsequence

Input format:
The first line of input contains an integer ‘T’ denoting the number of test cases.
The next ‘2*T’ lines represent the ‘T’ test cases.

The first line of each test case contains two space-separated integers the first integer ‘N’ will denote the number of elements in the array and the second integer denotes integer ‘K’.

The second line of each test case contains ‘N’ space-separated integer that is elements of the array.
Output Format
For each test case, print an integer that is the count of all subarray that sum is divisible by ‘K’.
Note:
You are not required to print the output explicitly, it has already been taken care of. Just implement the function.
Constraints:
1 <= T <= 50
1 <= K,N <= 10^4
-10^9 <= ARR[i] <= 10^9

Time limit: 1 second
AnswerBot
1y

The task is to count the number of subarrays in an array whose sum is divisible by a given integer.

  • Iterate through the array and calculate the cumulative sum at each index.

  • Store the remainder of each ...read more

CodingNinjas
author
2y
Brute Force (Time Limit Exceed)

The basic idea is that try each and every possible subarray and find the sum of the current subarray and check if the current sum is divisible by ‘K’.

  • To implement this...read more
CodingNinjas
author
2y
Prefix Sum

Let’s consider the sum of subarray ( ‘i’ to ‘j’ ) is divisible by ‘K’ and we can represent the sum of a subarray ( ‘i’ to ‘j’ ) = ( subarray sum (‘0’ to ‘j’ ) - subarray sum ( ‘0’ to ‘i-1’) ...read more

CodingNinjas
author
2y
Hashing

Let’s consider the sum of subarray ( ‘i’ to ‘j’ ) is divisible by ‘K’ and we can represent the sum of a subarray ( ‘i’ to ‘j’ ) = ( subarray sum (‘0’ to ‘j’ ) - subarray sum ( ‘0’ to ‘i-1’) ). ...read more

Add answer anonymously...
Protium Finance Software Developer Interview Questions
Stay ahead in your career. Get AmbitionBox app
qr-code
Helping over 1 Crore job seekers every month in choosing their right fit company
65 L+

Reviews

4 L+

Interviews

4 Cr+

Salaries

1 Cr+

Users/Month

Contribute to help millions
Get AmbitionBox app

Made with ❤️ in India. Trademarks belong to their respective owners. All rights reserved © 2024 Info Edge (India) Ltd.

Follow us
  • Youtube
  • Instagram
  • LinkedIn
  • Facebook
  • Twitter