#include <bits/stdc++.h>
using namespace std;

#ifdef _WIN32
#define scanfll(x) scanf("%I64d", x)
#define printfll(x) printf("%I64d", x)
#else
#define scanfll(x) scanf("%lld", x)
#define printfll(x) printf("%lld", x)
#endif
#define rep(i,n) for(long long i = 0; i < (long long)(n); i++)
#define repi(i,a,b) for(long long i = (long long)(a); i < (long long)(b); i++)
#define pb push_back
#define all(x) (x).begin(), (x).end()
#define fi first
#define se second
#define mt make_tuple
#define mp make_pair
template<class T1, class T2> bool chmin(T1 &a, T2 b) { return b < a && (a = b, true); }
template<class T1, class T2> bool chmax(T1 &a, T2 b) { return a < b && (a = b, true); }

using ll = long long; using ld = long double; using vll = vector<ll>; using vvll = vector<vll>; using vld = vector<ld>; 
using vi = vector<int>; using vvi = vector<vi>;
vll conv(vi& v) { vll r(v.size()); rep(i, v.size()) r[i] = v[i]; return r; }
using P = pair<ll, ll>;

template <typename T, typename U> ostream &operator<<(ostream &o, const pair<T, U> &v) {  o << "(" << v.first << ", " << v.second << ")"; return o; }
template<size_t...> struct seq{}; template<size_t N, size_t... Is> struct gen_seq : gen_seq<N-1, N-1, Is...>{}; template<size_t... Is> struct gen_seq<0, Is...> : seq<Is...>{};
template<class Ch, class Tr, class Tuple, size_t... Is>
void print_tuple(basic_ostream<Ch,Tr>& os, Tuple const& t, seq<Is...>){ using s = int[]; (void)s{0, (void(os << (Is == 0? "" : ", ") << get<Is>(t)), 0)...}; }
template<class Ch, class Tr, class... Args> 
auto operator<<(basic_ostream<Ch, Tr>& os, tuple<Args...> const& t) -> basic_ostream<Ch, Tr>& { os << "("; print_tuple(os, t, gen_seq<sizeof...(Args)>()); return os << ")"; }
ostream &operator<<(ostream &o, const vvll &v) { rep(i, v.size()) { rep(j, v[i].size()) o << v[i][j] << " "; cout << endl; } return o; }
template <typename T> ostream &operator<<(ostream &o, const vector<T> &v) { o << '['; rep(i, v.size()) o << v[i] << (i != v.size()-1 ? ", " : ""); o << "]";  return o; }
template <typename T>  ostream &operator<<(ostream &o, const set<T> &m) { o << '['; for (auto it = m.begin(); it != m.end(); it++) o << *it << (next(it) != m.end() ? ", " : ""); o << "]";  return o; }
template <typename T, typename U>  ostream &operator<<(ostream &o, const map<T, U> &m) { o << '['; for (auto it = m.begin(); it != m.end(); it++) o << *it << (next(it) != m.end() ? ", " : ""); o << "]";  return o; }
template <typename T, typename U>  ostream &operator<<(ostream &o, const unordered_map<T, U> &m) { o << '['; for (auto it = m.begin(); it != m.end(); it++) o << *it; o << "]";  return o; }
void printbits(ll mask, ll n) { rep(i, n) { cout << !!(mask & (1ll << i)); } cout << endl; }
#define ldout fixed << setprecision(40) 

static const double EPS = 1e-14;
static const long long INF = 1e18;
static const long long mo = 1e9+7;

ll n, k;
vvll g; 
ll min_dist(vector<bool>& used, ll initial_v, ll initial_k) {
    function<void(ll, ll)> f = [&](ll v, ll ks) {
        if (initial_k < ks) return;
        if (used[v]) return;
        used[v] = 1;
//        cout << v << ":" << g[v] << endl;
        for (auto to : g[v]) {
            f(to, ks+1);
        }
    }; 
    f(initial_v, 0);
    ll s = 0;
    rep(i, n) {
        s += used[i];
    }
    return s;
}

int main(void) {
    cin.tie(0); ios::sync_with_stdio(false);
    cin >> n >> k;
    g = vvll(n);
    vector<P> es; 
    rep(i, n-1) {
        ll u, v; cin >> u >> v; u--; v--;
        g[u].pb(v);
        g[v].pb(u);
        es.pb(P(u, v));
    }


    ll ret = INF;
    if (k % 2 == 0) {
        rep(v, n) {
            vector<bool> used(n);
            ll tmp = min_dist(used, v, k/2);
//            cout << tmp << endl;
//            cout << used << endl;
            chmin(ret, n - tmp);
        }
    } else {
        for (auto e : es) {
            vector<bool> used(n);
//            cout << e << ":" << endl;

            ll tmp = 0;
            rep(i, n) used[i] = 0;
            used[e.fi] = 1;
            tmp += min_dist(used, e.se, (k-1)/2) - 1;
           
            rep(i, n) used[i] = 0;
            used[e.se] = 1;
            tmp += min_dist(used, e.fi, (k-1)/2) - 1;
//            cout << tmp << endl;
//            cout << used << endl;

            chmin(ret, n - tmp);
        }
    }
    cout << ret << endl;

    return 0;
}


Measured memory_bytes: 512