Code Submission Evaluation System Login

CSES Problem Set

Creating Offices


Task | Statistics


CSES - Creating OfficesCSES - Creating Offices

Time limit:1.00 s Memory limit:512 MB

There are $n$ cities and $n-1$ roads between them. There is a unique route between any two cities, and their distance is the number of roads on that route.

A company wants to have offices in some cities, but the distance between any two offices has to be at least $d$. What is the maximum number of offices they can have?

Input

The first input line has two integers $n$ and $d$: the number of cities and the minimum distance. The cities are numbered $1,2,\dots,n$.

After this, there are $n-1$ lines describing the roads. Each line has two integers $a$ and $b$: there is a road between cities $a$ and $b$.

Output

First print an integer $k$: the maximum number of offices. After that, print the cities which will have offices. You can print any valid solution.

Constraints
Example

Input:
5 3
1 2
2 3
3 4
3 5


Output:
2
1 4