#include<iostream>
#include <queue>
#define ll long long int 
using namespace std;
int main(){
	ll n,r,c;
	cin>>n;
	ll g[n][n],visited[n],lastnode,sum=0,a,b;
	for(ll i=0;i<n;i++)
		for(ll j=0;j<n;j++)
			if(i==j)
				g[i][j]=0;
			else	
				g[i][j]=-1;
	for(ll i=0;i<n-1;i++){
		cin>>a>>b;
		g[a-1][b-1]=1;
		g[b-1][a-1]=1;
	}
	for(ll i=0;i<n;i++)
		visited[i]=0;
	queue<ll> q;
	q.push(0);
	visited[0]=1;
		while(!q.empty()){
	    	r=q.front();
			q.pop();
			for(ll i=0;i<n;i++)
				if(g[r][i]==1 && !visited[i]){
					q.push(i);
					visited[i]=1;
				}
	}
	lastnode=r;
	for(ll i=0;i<n;i++)
		visited[i]=0;
	visited[r]=1;
	q.push(r);
	while(!q.empty()){
		lastnode=q.front();
		q.pop();
		c=0;
		for(ll i=0;i<n;i++)
			if(g[lastnode][i]==1 && !visited[i]){
				if(c==0){
					sum++;
					c=1;
				}
				visited[i]=1;
				q.push(i);
				}
	}
	cout<<sum;
	return 0;
}