Added solution for Problem Equal in java

[rishuverma]

Pull Request Template

Description

Adding my solution to problem 'Equal' in the algorithm section of Hackerrank. link: https://www.hackerrank.com/challenges/equal/problem
The code is properly commented for understanding the solution.
If running in the local machine make sure JDK is installed. No dependency if using an online java compiler.

Fixes # (issue)
The solution to a Hackerrank question.

How Has This Been Tested?

The solution passes all test cases in Hackerrank.

Please describe the tests that you ran to verify your changes. Please also note any relevant details for your test configuration.

• Test A: passes all Hackerank test cases.

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• Any dependent changes have been merged and published in downstream modules