#include <bits/stdc++.h>
using namespace std;
const int N = 2e5 + 69;
int n, dp[N][2];
vector<int> g[N];
void dfs(int v, int p) {
	for (auto u : g[v]) {
		if (u == p)
			continue;
		dfs(u, v);
		dp[v][0] = max(dp[v][0], max(dp[u][1], dp[u][0]));
		dp[v][1] = max(dp[v][1], dp[u][0] + 1);
	}
}
int main() {
	ios::sync_with_stdio(false);
	cin.tie(0);
	int n;
	cin >> n;
	for (int i = 1;i <= n - 1;i++) {
		int a, b;
		cin >> a >> b;
		g[a].push_back(b);
		g[b].push_back(a);
	}
	dfs(1, 0);
	int m = max(dp[1][1], dp[1][0]);
	cout << 2 * n - 3 * m << endl;
}