#include <bits/stdc++.h>

#define MAXN 1005

int N, K;
std::vector <int> ADC[MAXN];

inline void AddEdge(int X, int Y) {
    ADC[X].push_back(Y);
    ADC[Y].push_back(X);
}

int SavePoints, Ans;
int DP[MAXN], Count[MAXN], DPBound;
bool Flag[MAXN];
void DFS(int Vertex = 1, int Parent = 0) {
    for (auto Edge:ADC[Vertex])
        if (Edge != Parent)
            DFS(Edge, Vertex);
    DP[Vertex] = MAXN;
    Count[Vertex] = DPBound;

    for (auto Edge:ADC[Vertex])
        if (Edge != Parent)
            DP[Vertex] = std::min(DP[Vertex], DP[Edge] + 1),
            Count[Vertex] = std::min(Count[Vertex], Count[Edge] - 1);

    if (DP[Vertex] <= Count[Vertex])
        Count[Vertex] = MAXN;
    if (!Count[Vertex])
        ++SavePoints, Flag[Vertex] = 1,
        Count[Vertex] = MAXN, DP[Vertex] = 0;
}

std::ifstream In ("salvare.in");
std::ofstream Out("salvare.out");

bool Check(int Bound) {
    SavePoints = 0;
    DPBound = Bound;
    for (int i=1; i<=N; ++i)
        DP[i] = Flag[i] = 0;

    DFS();
    return (SavePoints <= K);
}

void Citire() {
    In >> N >> K;
    for (int i=1, X, Y; i<N; ++i)
        In >> X >> Y, AddEdge(X, Y);
}

void Rezolvare() {
    int lbound = 1, rbound = N, mid;
    while (lbound <= rbound) {
        mid = (lbound + rbound)/2;
        if (Check(mid))
            Ans = mid, rbound = mid-1;
        else
            lbound = mid+1;
    }   Out << Ans << '\n';
    Check(Ans);

    int idx = 1;
    while (SavePoints < K) {
        while (Flag[idx]) ++ idx;
        Flag[idx] = 1;
        ++ SavePoints;
    }

    for (int i=1; i<=N; ++i)
        if (Flag[i])
            Out << i << ' ';
}

int main()
{
    Citire();
    Rezolvare();

    return 0;
}