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

#define int long long

signed main(){
	ios::sync_with_stdio(false);
	cin.tie(nullptr);
#ifndef ONLINE_JUDGE
	freopen("be1.txt","r",stdin);
#endif
	int N;
	cin>>N;
	vector<vector<int>>g(N+1);
	for(int i=0;i<N-1;i++){
		int a,b;
		cin>>a>>b;
		g[a].push_back(b);
		g[b].push_back(a);
	}
	vector<int>s(N+1),a(N+1),b(N+1),c(N+1);
	auto dfs=[&](auto self,int i)->void{
		s[i]=1;
		for(int j:g[i]){
			if(s[j]){
				continue;
			}
			self(self,j);
			s[i]+=s[j];
			c[i]+=c[j];
			int x=b[j]+s[j]*2+c[j];
			int y=a[j]+8;
			if(y<x){
				a[i]+=y;
				c[i]+=4;
			}
			else{
				a[i]+=x;
			}
			b[i]+=min(x,y);
		}
	};
	dfs(dfs,1);
	cout<<a[1]<<'\n';
	return 0;
}