LA 3524

LA 3524 - The Cow Doctor

 * http://acmicpc-live-archive.uva.es/nuevoportal/data/problem.php?p=3524

Summary
The doctor has some test materials. Each test material can test a set of diseases. A mixture of two test materials gives a new test material that can test diseases at least one of the mixed materials tested.

Given is a set of test materials. Determine, how many of them are redundant, i.e., can be obtained by mixing some other test materials.

Explanation
This problem is pretty straightforward.

How to check whether a given test material M is redundant? Consider the set S of all other test materials that test a subset of M's diseases. M is redundant if and only if the mixture of all materials in S tests exactly the same set of diseases as M.

Implementations
It is convenient to represent the materials as bit vectors.

Input
10 5 2 1 2 2 2 3 3 1 2 3 4 1 2 3 4 1 4 3 7 1 1 1 2 1 3 2 1 2 2 1 3 2 3 2 3 1 2 3

Output
2 4