kobuqa/mbicycle-algorithmic-task

Welcome, candidate! 👋

In that repository you can find our screening pre-interview task

Yes, I know, it's boring to solve tasks like that. But it's not my personal wish or will. Customers provide their own tasks in hackerrank and most of interviews are failed cuz of that. Hope you will understand.

Task: Sum in Range

Given an array arr of integers, and two l and r, find the number of pairs (i, j)(1 <= i < j <= n) such that value arr[i][] + arr[j][] lies between l and r, both inclusive. Array indices starts at 1.

Example

Suppose n = 4, arr = [2, 3, 4, 5], l = 5, r = 7

There are 4 pairs with a sum between 5 and 7:

• arr[1] + arr[2] = 2 + 3 = 5
• arr[1] + arr[3] = 2 + 4 = 6
• arr[1] + arr[4] = 2 + 5 = 7
• arr[2] + arr[3] = 3 + 4 = 7

!NB - avoid duplicates. (2 + 4 is same pair with 4 + 2)

!!NB - avoid time complexity of O(n^2)

Return 4.

Function description

Complete the function getNumPairs.

The function getNumPairs has the following signature:

• int arr(n): an array of integers
• int l: minimum acceptable sum
• int r: maximum acceptable sum

Return

int: the number of pairs that satisfy the condition.

Constraints

• 1 <= n <= 10^5
• 1 <= arr[i] <= 10^9
• 0 <= l <= r <= 10^9

Feel free to open index.js and write your own solution.

After finishing the solution create new pull request to current repo & tag me as reviewer (@kobuqa).

Wish you good luck! 🍀

Test your solution

1. npm i

2. npm test