add new medium and hard level problem

[Tarunagg1]

the problem should be taken from leetcode,gfg ot any other website.

1. Add description of problem comment it in file
2. Add solution
3. Code should be proper

Definitely merge if problem and code is proper

[Utkarsh2312]

Please assign this task to me.

[bhavyagupta-11]

Kindly assign this issue to me!