Add README.md file

[saurabh47]

Add README.md file for all the missing programs.
Every program folder should contain README.md.
README.md file should contain problem statement & description.

[EANimesha]

Can I contribute to this? Assign me

[saurabh47]

@EANimesha , I have assigned this issue to you.

[saurabh47]

@EANimesha Please let me know if you are not working on this issue. I will assign this to someone else.