#include <bits/stdc++.h>
using namespace std;
#define ff endl
#define lf "\n"
#define fi first
#define se second
#define _ << ' ' <<
#define all(x) begin(x),end(x)
#define rall(x) rbegin(x),rend(x)
#ifdef DEBUG
constexpr bool IS_DEBUG = 1;
#define infor(fmt, ...) do { print(stderr, fmt, ##__VA_ARGS__); } while(0)
#define infof(fmt, ...) do { println(stderr, fmt, ##__VA_ARGS__); } while(0)
#else
constexpr bool IS_DEBUG = 0;
#define infor(fmt, ...)
#define infof(fmt, ...)
#endif
using ll = long long;
using pll = pair<ll, ll>;
using pii = pair<int, int>;
template<typename... Args>
using vec = vector<Args...>;
mt19937 timmy_loves_gambling(73);
struct TreeHasher {
TreeHasher(void): id(0) {
m.emplace(vec<int>(), id++);
}
int hash(vec<int> &T) {
sort(all(T));
if(!m.count(T)) {
m[T] = id++;
}
return m[T];
}
int id;
map<vec<int>, int> m;
};
int main(void) {
ios::sync_with_stdio(0);
cin.tie(0); cout.tie(0);
int N, M; cin >> N >> M;
vec<vec<int>> adj(N);
for(int i = 1; i < N; ++i) {
int u, v; cin >> u >> v;
u -= 1, v -= 1;
adj[u].emplace_back(v);
adj[v].emplace_back(u);
}
TreeHasher H;
vec<ll> szs(N);
vec<int> p(N), h(N), sz(N), cnt(N);
auto dfs = [&](int u, auto &&dfs) -> void {
sz[u] = 1;
vec<int> T;
for(auto v: adj[u]) {
if(v == p[u]) continue;
p[v] = u;
dfs(v, dfs);
sz[u] += sz[v];
szs[u] += szs[v];
T.emplace_back(h[v]);
}
szs[u] += sz[u];
h[u] = H.hash(T);
cnt[h[u]] += 1;
};
p[0] = -1;
dfs(0, dfs);
infof(" p: {}", p);
infof(" h: {}", h);
infof(" sz: {}", sz);
infof("cnt: {}", cnt);
vec<int> ch;
vec<ll> chsz(N);
auto dfs2 = [&](int u, int d, auto &&dfs2) -> void {
ch.emplace_back(h[u]);
chsz[h[u]] += d;
for(auto v: adj[u]) {
if(v == p[u]) continue;
dfs2(v, d + 1, dfs2);
}
};
int ans = 0;
vec<bool> vis(N);
for(int i = 0; i < N; ++i) {
if(szs[i] != N - M || vis[h[i]]) continue;
vis[h[i]] = 1;
infof("===== i = {} | h = {} =====", i, h[i]);
dfs2(i, 1, dfs2);
infof(" ch: {}", ch);
infof("chsz: {}", chsz);
bool ok = 1;
for(auto x: ch) {
ok &= cnt[x] >= chsz[x];
}
for(auto x: ch) {
chsz[x] = 0;
}
ch.clear();
ans += ok;
}
cout << ans << lf;
}
