Hi

Its been a while that I've made some video on competitive programming.

The problem that I want to talk about today is:

You are given an array *A* of size *N* < 1000 with elements upto 10^{18}.

You have to print any subset *S* such that:

1. The AND resultant of all elements in *S* is 0.

2. The AND resultant of any 2 elements in *S* is not 0.

The problem looks easy but is quite twisted, and can be solved once you pick up the hidden observation here.

I read this problem sometime back in Petr's blog and wanted to share the solution with you guys.

Check out the video here: https://goo.gl/Pu9gZQ

Its difficult to pick up such observations but this is what I like about Competitive Programming. It makes you smarter gradually and you start looking at things in a different manner.

Happy Coding!