#include <bits/stdc++.h>
using namespace std;
//using namespace atcoder;
struct fast_ios { fast_ios(){ cin.tie(0); ios::sync_with_stdio(false); cout << fixed << setprecision(20); }; } fast_ios_;
#define FOR(i, begin, end) for(int i=(begin);i<(end);i++)
#define REP(i, n) FOR(i,0,n)
#define IFOR(i, begin, end) for(int i=(end)-1;i>=(begin);i--)
#define IREP(i, n) IFOR(i,0,n)
#define Sort(v) sort(v.begin(), v.end())
#define Reverse(v) reverse(v.begin(), v.end())
#define all(v) v.begin(),v.end()
#define SZ(v) ((int)v.size())
#define Lower_bound(v, x) distance(v.begin(), lower_bound(v.begin(), v.end(), x))
#define Upper_bound(v, x) distance(v.begin(), upper_bound(v.begin(), v.end(), x))
#define chmax(a, b) a = max(a, b)
#define chmin(a, b) a = min(a, b)
#define bit(n) (1LL<<(n))
#define debug(x) cout << #x << "=" << x << endl;
#define vdebug(v) { cout << #v << "=" << endl; REP(i_debug, v.size()){ cout << v[i_debug] << ","; } cout << endl; }
#define mdebug(m) { cout << #m << "=" << endl; REP(i_debug, m.size()){ REP(j_debug, m[i_debug].size()){ cout << m[i_debug][j_debug] << ","; } cout << endl;} }
#define pb push_back
#define fi first
#define se second
#define int long long
#define INF 1000000000000000000
template<typename T> istream &operator>>(istream &is, vector<T> &v){ for (auto &x : v) is >> x; return is; }
template<typename T> ostream &operator<<(ostream &os, vector<T> &v){ for(int i = 0; i < v.size(); i++) { cout << v[i]; if(i != v.size() - 1) cout << endl; }; return os; }
template<typename T1, typename T2> ostream &operator<<(ostream &os, pair<T1, T2> p){ cout << '(' << p.first << ',' << p.second << ')'; return os; }
template<typename T> void Out(T x) { cout << x << endl; }
template<typename T1, typename T2> void chOut(bool f, T1 y, T2 n) { if(f) Out(y); else Out(n); }

using vec = vector<int>;
using mat = vector<vec>;
using Pii = pair<int, int>;
using v_bool = vector<bool>;
using v_Pii = vector<Pii>;

//int dx[4] = {1,0,-1,0};
//int dy[4] = {0,1,0,-1};
//char d[4] = {'D','R','U','L'};

const int mod = 1000000007;
//const int mod = 998244353;

struct edge{int to, cost, id;};

class Graph
{
public:
    int N;
    vector<vector<edge>> G;
    vec dp, dq;

    Graph(int N): N(N){
        G = vector<vector<edge>>(N, vector<edge>(0));
        dp.resize(N);
        dq.resize(N);
    }

    void add_Directed_edge(int from, int to, int cost = 1, int id = 0){
        G[from].push_back(edge({to, cost, id}));
    }

    void add_Undirected_edge(int v1, int v2, int cost = 1, int id = 0){
        add_Directed_edge(v1, v2, cost, id);
        add_Directed_edge(v2, v1, cost, id);
    }

    void dfs(int v, int T, int &num, int p = -1){
        dp[v] = T;
        dq[v] = -1;
        for(auto e: G[v]) if(e.to != p){
            dfs(e.to, T, num, v);
            if(dq[e.to] > 0){
                chmax(dq[v], dq[e.to] - 1);
            }else{
                chmin(dp[v], dp[e.to] - 1);
            }
        }
        if(dq[v] >= 0){
            if(dp[v] >= T - dq[v]) dp[v] = T + 1;
            else dq[v] = -1;
        }
        if(dp[v] == 0){
            num++;
            dq[v] = T;
        }
    }

};

signed main(){

    int K, N; cin >> N >> K;
    Graph G(N);
    REP(i, N - 1){
        int u, v; cin >> u >> v;
        u--; v--;
        G.add_Undirected_edge(u, v);
    }

    int T0 = 0, T1 = N;
    while(T1 - T0 > 1){
        int T = (T0 + T1) / 2;
        int num = 0;
        G.dfs(0, T, num);
        if(G.dq[0] == -1) num++;

        if(num <= K) T1 = T;
        else T0 = T;
    }
    Out(T1);

    return 0;
}

#include <bits/stdc++.h>

using namespace std;

int main() {
    ios::sync_with_stdio(0);
    cin.tie(0);
    int N, M;
    cin >> N >> M;
    vector<vector<array<int, 2>>> A(N + 1);
    for (int i = 0; i < M; i++) {
        int X, Y, Z;
        cin >> X >> Y >> Z;
        A[X].push_back({Y, Z});
    }
    vector<int64_t> dp(1<<N);
    dp[0] = 1;
    for (int i = 0; i < (1 << N); i++) {
        int n = __builtin_popcount(i);
        int valid = 1;
        for (auto u : A[n]) {
            int m = __builtin_popcount(i & ((1 << u[0]) - 1));
            if (m > u[1]) {
                valid = 0;
                break;
            }
        }
        if (valid) {
            for (int j = 0; j < N; j++) {
                if ((i & (1 << j)) == 0) continue;
                dp[i] += dp[i^(1<<j)];
            }
        }
    }
    cout << dp[(1<<N) - 1];
}