#include<fstream>
#include<vector>
#define DIM 1010
using namespace std;
ifstream fin("salvare.in");
ofstream fout("salvare.out");
int d[DIM],f[DIM];
vector<int> v[DIM];
int n,k,a,b,i,st,dr,l,mid;
void dfs(int nod, int val,int t)
{
    int mini=1000000000;d[nod]=0;
    for(auto vecin:v[nod])if(vecin!=t)
    {dfs(vecin,val,nod);d[nod]=max(d[nod],d[vecin]+1);mini=min(mini,d[vecin]+1);}
    if(d[nod]==val){l++,d[nod]=-val-1;f[nod]=1;return;}
    if(mini<0&&-mini-1>=d[nod]) d[nod]=mini;
}
int main()
{
    fin>>n>>k;
    for(i=1;i<n;i++)
    {
        fin>>a>>b;
        v[a].push_back(b);
        v[b].push_back(a);
    }
    st=1;dr=n*2;
    while(st<=dr)
    {
        mid=(st+dr)/2;l=0;dfs(1,mid,0);
        if(d[1]>=0){++l;f[1]=1;}
        if(l<=k)
            dr=mid-1;
        else
            st=mid+1;
    }
    fout<<st<<"\n";l=0;
    for(i=1;i<=n;i++) f[i]=0;
    dfs(1,st,0);if(d[1]>=0){++l;f[1]=1;}l=k-l;
    for(i=1;i<=n;i++)
        if(f[i]==1) fout<<i<<" ";
    else
        if(f[i]==0&&l){fout<<i<<" ";l--;}
    return 0;
}