Sherlock and array

[Mayank662]

Added a hackerrank problem with solution in C++, Please review it.
Fixes #15

[sunnysetia93]

Great.
But I see you are not following how to submit code on this repo.
Please go through contributions.md once.

Add this program in the category in which it belongs.

1. if its an array based question. create an Array folder in the directory (HackerRank_Problems/ProblemSolving/cppSolutions/)
2. Then create a file named sherlockAndArray.cpp containing the code.
3. No need to copy-paste the entire question from hacker-rank, just paste the link of question in comments above the code.
4. add a starter code, how to call your function/class with desired params and then give the expected output in comments in the same line.
5. Refer to this file:

   competitive-coding-problems/LeetCode/All/cpp/136.single-number.cpp

   Line 1 in b251320

   #include<bits/stdc++.h>

   
   These practice will make your code readable and will be easier for other's to maintain in future.

[sunnysetia93]

Closing this as @Mayank662 you have created a new PR #24