#include <bits/stdc++.h>

using namespace std;

const int Nmax = 1010;

int n , K , i , ret , nr;
int dist[Nmax] , ramas[Nmax];
bool marked[Nmax] , used[Nmax];

vector < int > ans , g[Nmax];

void dfs(int node , int prev , int k)
{
    for (auto &it : g[node])
        if (it != prev)
            dfs(it , node , k);

    dist[node] = Nmax; ramas[node] = k;
    for (auto &it : g[node])
        if (it != prev)
            dist[node] = min(dist[node] , dist[it] + 1),
            ramas[node] = min(ramas[node] , ramas[it] - 1);

    if (dist[node] <= ramas[node])
        ramas[node] = Nmax;
    if (!ramas[node])
        dist[node] = 0, ramas[node] = Nmax, marked[node] = 1;
}

bool check(int dist)
{
    memset(marked , 0 , sizeof(marked));

    dfs(1 , 0 , dist);
    for (ret = 0, i = 1; i <= n; ++i)
        if (marked[i]) ret++;

    return (ret <= K);
}

int search_()
{
    int i , j , step;

    for (step = 1; step < n; step <<= 1);

    for (i = n; step; step >>= 1)
        if (i - step >= 0 && check(i - step))
        {
            i -= step; nr = ret;
            memcpy(used , marked,  sizeof(marked));
        }

    for (j = 1; j <= n; ++j)
        if (used[j]) ans.push_back(j);
        else if (nr < K) ans.push_back(j), nr++;

    return i;
}

int main()
{
    freopen("salvare.in","r",stdin);
    freopen("salvare.out","w",stdout);

    scanf("%d %d", &n, &K);
    for (i = 1; i < n; ++i)
    {
        int x , y;
        scanf("%d %d", &x, &y);
        g[x].push_back(y);
        g[y].push_back(x);
    }

    printf("%d\n", search_());
    for (auto &it : ans)
        printf("%d ", it);

    return 0;
}