#include <iostream>
#include <vector>
#include "catdog.h"

using namespace std;

const int N = 1e5 + 5; 

int n, a[N];
vector<int> e[N];
int f[N][2];

void initialize (int N, vector<int> A, vector<int> B) {
  n = N;
  for (int i = 0; i < n; ++i) {
    e[A[i]].push_back(B[i]);
    e[B[i]].push_back(A[i]);
  }
}

void DP (int u, int r) {
  f[u][0] = f[u][1] = 0;
  for (auto v : e[u]) {
    if (v != r) {
      DP(v, u);
      f[u][0] += min(f[v][0], f[v][1] + 1);
      f[u][1] += min(f[v][1], f[v][0] + 1);
    }
  }
  if (a[u] == 1) f[u][0] = N;
  if (a[u] == 2) f[u][1] = N;
}

int Solve () {
  DP(1, 0);
  return min(f[1][0], f[1][1]);
}

int cat (int v) {
  a[v] = 1; 
  return Solve();
}

int dog (int v) {
  a[v] = 2;
  return Solve();
}

int neighbor (int v) {
  a[v] = 0; 
  return Solve();
}

// void Test () {
//   int N;
//   cin >> N;
//   vector<int> A(N), B(N);
//   for (int i = 0; i < N - 1; ++i) {
//     cin >> A[i] >> B[i];
//   }
//   initialize(N, A, B);
//   int Q;
//   cin >> Q;
//   for (int T, v; Q--; ) {
//     cin >> T >> v;
//     cout << (T == 1 ? cat : (T == 2 ? dog : neighbor))(v) << '\n';
//   }
// }

// int main () { Test(); }