Жишээ тэстүүд

Оролт
4 1
1 1 0 0
1 2
1 3
1 4
Гаралт
2
Оролт
7 1
1 0 1 1 0 0 0
1 2
1 3
2 4
2 5
3 6
3 7
Гаралт
2

Тэмдэглэл

Let us remind you that a tree$ is a connected graph on $n$ vertices and $n - 1$ edge. A rooted$ tree is a tree with a special vertex called root$. In a rooted tree among any two vertices connected by an edge, one vertex is a parent (the one closer to the root), and the other one is a child. A vertex is called a leaf$, if it has no children.

Note to the first sample test: The vertices containing cats are marked red. The restaurants are at vertices 2, 3, 4. Kefa can't go only to the restaurant located at vertex $2$.

Note to the second sample test: The restaurants are located at vertices 4, 5, 6, 7. Kefa can't go to restaurants 6, 7.