#include <bits/stdc++.h>

using namespace std;

#ifdef DEBUG
  #include "debug.hpp"
#else
  #define dbg(...) 0
#endif

int solve(const vector<vector<int>>& adj) {
  int n = adj.size();
  int inf = 3 * n;
  vector<int> parent(n, -1), order; order.reserve(n);
  {
    auto dfs = [&](auto&& self, int u, int pa) -> void {
      for (int v : adj[u]) if (v != pa) {
        parent [v] = u;
        self(self, v, u);
      }
      order.push_back(u);
    };
    dfs(dfs, 0, -1);
  }
  vector<vector<int>> children(n);
  for (int i = 0; i < n; ++i) if (parent[i] >= 0) {
    children[parent[i]].push_back(i);
  }
  vector<pair<int, int>> dp(n);
  for (int u : order) {
    const vector<int>& ch = children[u];
    int nch = ch.size();
    if (nch == 0) {
      dp[u] = {2, 0};
      continue;
    }
    int sum0 = 0;
    int min1 = numeric_limits<int>::max();
    for (int v : ch) {
      sum0 += dp[v].first;
      min1 = min(min1, dp[v].second - dp[v].first);
    }
    dp[u] = {min(2 + sum0, 1 + sum0 + min1), sum0};
  }
  int ans = dp[0].first;
  vector<pair<int, int>> dp2(n);
  dp2[0] = {0, 0};
  reverse(order.begin(), order.end());
  for (int u : order) {
    const vector<int>& ch = children[u];
    int nch = ch.size();
    vector<int> prefix_min(n + 1, inf), suffix_min(n + 1, inf);
    int sum0 = dp2[u].first;
    for (int i = 0; i < nch; ++i) {
      prefix_min[i + 1] = min(prefix_min[i], dp[ch[i]].second - dp[ch[i]].first);
      sum0 += dp[ch[i]].first;
    }
    for (int i = nch - 1; i >= 0; --i) {
      suffix_min[i] = min(suffix_min[i + 1], dp[ch[i]].second - dp[ch[i]].first);
    }
    for (int i = 0; i < nch; ++i) {
      int v = ch[i];
      dp2[v] = {min(2 + sum0 - dp[v].first, 1 + sum0 - dp[v].first + min(prefix_min[i], suffix_min[i + 1])), sum0 - dp[v].first};
    }
  }
  for (int u = 1; u < n; ++u) {
    int sum0 = dp2[u].first;
    int min1 = dp2[u].second - dp2[u].first;
    for (int v : children[u]) {
      sum0 += dp[v].first;
      min1 = min(min1, dp[v].second - dp[v].first);
    }
    ans = min(ans, min(2 + sum0, 1 + sum0 + min1));
  }
  return ans;
}

int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  int n;
  cin >> n;
  vector<vector<int>> adj(n);
  for (int i = 1; i < n; ++i) {
    int u, v;
    cin >> u >> v;
    --u; --v;
    adj[u].push_back(v);
    adj[v].push_back(u);
  }
  cout << solve(adj) << '\n';
}