I was going through the problem statement for 2019 Google Hash Code Finals. I am just wondering how to approach this problem. Can someone help me?

Thanks

I've seen people with negative contributions but all their blog entries and comments have net positive votes.

Can someone help me with this problem.

Given an array A of N numbers. We are required to find the size of the smallest subset of the array such that Bitwise OR is maximum possible.

$$$1 \leq N \leq 10^5$$$

$$$1 \leq A[i] \leq 10^6$$$

Sample input:
5
1 2 3 4 5

Sample output:
2