#include <cstdio>
#include <vector>
using namespace std;
#define NMAX 100100
#define MIN(a,b) (((a)<(b))?(a):(b))
#define pb push_back
vector<long long> C[NMAX];
vector<int> A[NMAX];
int N, K, MinK, X[NMAX], Fr[NMAX], F[NMAX], tata[NMAX], nq;
int R[NMAX], G[NMAX], g[NMAX];
long long BIG, Cmin, lo, hi, md, B[NMAX], Q[NMAX], V[NMAX], Cost[NMAX];
void dfs(int i)
{
int j, n = A[i].size();
F[i] = 1;
for (j = 0; j < n; j++)
if (!F[ A[i][j] ])
{
tata[ A[i][j] ] = i;
Cost[ A[i][j] ] = C[i][j];
dfs(A[i][j]);
}
}
void _try()
{
int i, k, j, n;
for (k = 0; k < nq; k++)
{
i = Q[k]; n = A[i].size();
for (j = 0; j < n; j++)
V[i] = MIN(V[i], V[ A[i][j] ]-C[i][j]*B[ A[i][j] ]);
if (V[i]<=0)
{
X[i] = 1;
V[i] = 1+(md<<1);
MinK++;
}
G[ tata[i] ]--;
if (G[ tata[i] ]==1) Q[nq++] = tata[i];
}
}
int main()
{
int i, j, k, nf=0, t;
long long a = 1000000000, b = 1000000;
BIG = a*b;
freopen("salvare.in", "r", stdin);
freopen("salvare.out", "w", stdout);
scanf("%d%d", &N, &K);
for (t = 1; t <= N; t++) B[t] = 1;
for (t = 1; t < N; t++)
{
scanf("%d%d", &i, &j); k = 1;
A[i].pb(j); A[j].pb(i); C[i].pb(k); C[j].pb(k);
G[i]++; G[j]++;
}
for (i = 1; i <= N; i++) g[i] = G[i];
dfs(1);
for (i = 1; i <= N; i++)
if (G[i]==1) Fr[nf++] = i;
md = BIG/2;
for (lo = 0, hi = BIG; lo <= hi; md = (lo+hi)>>1)
{
for (i = 1; i <= N; i++) V[i] = BIG, X[i] = 0, G[i] = g[i];
for (i = nq = 0; i < nf; i++)
Q[nq++] = Fr[i], V[ Fr[i] ] = md;
MinK = 0;
_try();
if (MinK <= K) hi = md-1, Cmin = md;
else lo = md+1;
}
md = Cmin;
for (i = 1; i <= N; i++) V[i] = BIG, X[i] = 0, G[i] = g[i];
for (i = nq = 0; i < nf; i++)
Q[nq++] = Fr[i], V[ Fr[i] ] = md;
MinK = 0;
_try();
for (i = 1; i <= N && MinK < K; i++)
if (!X[i]) X[i] = 1, MinK++;
printf("%lld\n", Cmin);
for (i = 1; i <= N; i++)
if (X[i]) printf("%d ", i);
printf("\n");
return 0;
}