##### Hiring Admins

enigma is hiring new admins to maintain PNOJ while he goes on vacation to Wuhan during the break!

PNOJ has $$M$$ different staff positions, numbered $$1$$ to $$M$$. Each staff position can only be occupied by one person.

Since enigma is in a hurry, he doesn't have time to evaluate the administrative abilites of all $$N$$ people each applying for some subset of the $$M$$ total positions (That would take $$O(MN)$$!).

Instead, help him determine the maximum amount of positions that can be filled from the $$N$$ people.

### Constraints

For 10% of the points, $$1\le N, M\le 10$$.

### Input Specification

The first line contains $$N$$ ($$1\le N\le 100$$) and $$M$$ ($$1\le M\le 100$$), followed by $$N$$ lines.

The ith line contains $$S_i$$ ($$0\le Si\le M$$), the number of positions the $$i$$th staff member is applying for, followed by $$S_i$$ integers, the positions.

### Output Specification

Output on one line the maximum number of positions enigma can fill by hiring each person for at most one position.

### Sample Input

6 62 2 302 1 41 32 3 41 6

### Sample Output

5`
Comments
• There are no comments.