- Time limit: 1.00 s
- Memory limit: 512 MB
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?
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 $b$.
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.
- $1 \le n,d \le 2 \cdot 10^5$
- $1 \le a,b \le n$