#include <bits/stdc++.h>
using namespace std;
const int MOD = (int)1e9 + 7;
const int INF = (int)1e9;
const long long LINF = (long long)1e18;
const long double PI = acos((long double)-1);
const long double EPS = 1e-9;
inline long long gcd(long long a, long long b) {
  long long r;
  while (b) {
    r = a % b;
    a = b;
    b = r;
  }
  return a;
}
inline long long lcm(long long a, long long b) { return a / gcd(a, b) * b; }
inline long long fpow(long long n, long long k, int p = MOD) {
  long long r = 1;
  for (; k; k >>= 1) {
    if (k & 1) r = r * n % p;
    n = n * n % p;
  }
  return r;
}
template <class T>
inline int chkmin(T& a, const T& val) {
  return val < a ? a = val, 1 : 0;
}
template <class T>
inline int chkmax(T& a, const T& val) {
  return a < val ? a = val, 1 : 0;
}
inline long long isqrt(long long k) {
  long long r = sqrt(k) + 1;
  while (r * r > k) r--;
  return r;
}
inline long long icbrt(long long k) {
  long long r = cbrt(k) + 1;
  while (r * r * r > k) r--;
  return r;
}
inline void addmod(int& a, int val, int p = MOD) {
  if ((a = (a + val)) >= p) a -= p;
}
inline void submod(int& a, int val, int p = MOD) {
  if ((a = (a - val)) < 0) a += p;
}
inline int mult(int a, int b, int p = MOD) { return (long long)a * b % p; }
inline int inv(int a, int p = MOD) { return fpow(a, p - 2, p); }
const int maxn = 100000 + 10;
int n;
vector<pair<int, int> > adj[maxn];
pair<int, int> edge[maxn << 1];
int f[maxn << 1];
int cnt;
map<vector<int>, int> hs, hs2;
int dfs(int e) {
  int& res = f[e];
  if (~res) return res;
  int u = edge[e].second;
  vector<int> vv;
  for (int i = (0); i < (int((adj[u]).size())); i++) {
    int v = adj[u][i].first;
    int w = adj[u][i].second;
    if (w != (e ^ 1)) {
      vv.push_back(dfs(w));
    }
  }
  sort((vv).begin(), (vv).end());
  if (hs.count(vv)) return res = hs[vv];
  res = int((hs).size());
  return hs[vv] = res;
}
void solve() {
  cin >> n;
  for (int i = (0); i < (n - 1); i++) {
    int u, v;
    cin >> u >> v;
    u--, v--;
    adj[u].push_back(make_pair(v, i << 1));
    adj[v].push_back(make_pair(u, i << 1 | 1));
    edge[i << 1] = make_pair(u, v);
    edge[i << 1 | 1] = make_pair(v, u);
  }
  fill_n(f, n - 1 << 1, -1);
  for (int e = (0); e < (n - 1 << 1); e++) dfs(e);
  int ans = 0;
  for (int u = (0); u < (n); u++)
    if (int((adj[u]).size()) < 4) {
      vector<int> vv;
      for (int i = (0); i < (int((adj[u]).size())); i++) {
        int w = adj[u][i].second;
        vv.push_back(f[w]);
      }
      vv.push_back(0);
      sort((vv).begin(), (vv).end());
      hs2[vv];
    }
  cout << int((hs2).size()) << "\n";
}
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  solve();
  return 0;
}
