Grokking the Coding Interview: Patterns for Coding Questions
Ask Author
Back to course home

0% completed

Vote For New Content
Subarray Sums Divisible by K (medium)
Table of Contents

Contents are not accessible

Contents are not accessible

Contents are not accessible

Contents are not accessible

Contents are not accessible

Problem Statement

Given an array of integers nums and an integer k, return the count of non-empty subarrays that have a sum that is divisible by k.

A subarray is a continuous part of an array.

Examples

Example 1

  • Input: nums = [3, 1, 2, -2, 5, -1], k = 3
  • Expected Output: 7
  • Justification: The subarrays that sum to a multiple of 3 are [3], [1, 2], [3, 1, 2], [3, 1, 2, -2, 5], [1, 2, -2, 5], [-2, 5], and [2, -2].

Example 2

  • Input: nums = [4, 5, 0, -2, -3, 1], k = 5
  • Expected Output: 7
  • Justification: The subarrays that sum to a multiple of 5 are [5], [4, 5, 0, -2, -3, 1], [5, 0], [0], [5, 0, -2, -3], [0, -2, -3], and [-2, -3].

Example 3

  • Input: nums = [-1, 2, 9], k = 2
  • Expected Output: 2
  • Justification: The subarrays that sum to a multiple of 2 are [2] and [-1, 2, 9].

Constraints:

  • 1 <= nums.length <= 3 * 10<sup>4</sup>
  • -10<sup>4</sup> <= nums[i] <= 10<sup>4</sup>
  • 2 <= k <= 10<sup>4</sup>

Constraints:

  • 1 <= nums.length <= 3 * 10<sup>4</sup>
  • nums[i] is either 0 or 1.
  • 0 <= goal <= nums.length

Try it yourself

Try solving this question here:

Python3
Python3
. . . .

.....

.....

.....

Like the course? Get enrolled and start learning!

Table of Contents

Contents are not accessible

Contents are not accessible

Contents are not accessible

Contents are not accessible

Contents are not accessible