CSES - 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?


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.

  • $1 \le n,d \le 2 \cdot 10^5$
  • $1 \le a,b \le n$

5 3
1 2
2 3
3 4
3 5

1 4