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

using ll = long long;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
using vi = vector<int>;
using vl = vector<ll>;
#define rep3(i, a, b, c) for (ll i = (a); i < (b); i += (c))
#define rep2(i, a, b) rep3(i, a, b, 1)
#define rep1(i, n) rep2(i, 0, n)
#define rep0(n) rep1(aaaaa, n)
#define ov4(a, b, c, d, name, ...) name
#define rep(...) ov4(__VA_ARGS__, rep3, rep2, rep1, rep0)(__VA_ARGS__)
#define per(i, a, b) for (ll i = (a) - 1; i >= (b); i--)
#define fore(e, v) for (auto &&e : v)
#define all(a) begin(a), end(a)
#define sz(a) (int)(size(a))
#define lb(v, x) (lower_bound(all(v), x) - begin(v))
#define eb emplace_back

template <typename T, typename S> bool chmin(T &a, const S &b) {
  return a > b ? a = b, 1 : 0;
}
template <typename T, typename S> bool chmax(T &a, const S &b) {
  return a < b ? a = b, 1 : 0;
}
const int INF = 1e9 + 100;
const ll INFL = 3e18 + 100;
#define i128 __int128_t
struct _ {
  _() { cin.tie(0)->sync_with_stdio(0), cout.tie(0); }
} __;

const int MIN_N = 3, MAX_N = 100'000;

int main() {
  registerValidation();
  int N = inf.readInt(MIN_N, MAX_N);
  inf.readEoln();
  vector<vi> G(N);
  rep(N - 1) {
    int U = inf.readInt(1, N);
    inf.readSpace();
    int V = inf.readInt(1, N);
    inf.readEoln();
    ensure(U != V);
    --U, --V;
    G[U].push_back(V);
    G[V].push_back(U);
  }
  inf.readEof();
  vi ok(N);
  ok[0] = 1;
  queue<int> bfs;
  bfs.push(0);
  while (bfs.size()) {
    int v = bfs.front();
    bfs.pop();
    for (int u : G[v]) {
      if (!ok[u]) {
        ok[u] = 1;
        bfs.push(u);
      }
    }
  }
  ensure(accumulate(all(ok), 0) == N);
}