Solving HackerRank Problem: Beautiful Days at the Movies  using Java and javascript

Problem

Given a range of numbered days, [i..j] and a number k, determine the number of days in the range that are beautiful. Beautiful numbers are defined as numbers where | i - reverse(i) | is evenly divisible by k. If a day's value is a beautiful number, it is a beautiful day. Print the number of beautiful days in the range...

Complete the beautifulDays function in the editor below. It must return the number of beautiful days in the range...

See the full description of the problem Beautiful Days at the Movies

Solution

Simple brute-force is enough to solve this problem.  Run a loop from i to j and for each number x check if  abs(x - reverseOfX) % k === 0; if it does it's a  Beautiful day

Time complexity: O(n) //Iterate over each test case 

Space complexity: O(1) 

Credit: @github.com/RyanFehr