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#include<fstream>
#include<vector>
#include<bitset>
#include<queue>
#define Nmax 100099
using namespace std;
ifstream f("darb.in");
ofstream g("darb.out");
int n,x,y,d[Nmax],S,mare;
vector <int> G[Nmax];
bitset <Nmax> viz;
queue <int> Q;
void BFS(int S){
for(int i=1;i<=n;++i){
d[i]=0;
viz[i]=0;
}
d[S]=0;
viz[S]=1;
Q.push(S);
while(!Q.empty()){
int node=Q.front();
Q.pop();
vector <int> :: iterator it;
for(it=G[node].begin();it!=G[node].end();++it){
if(viz[*it]==0){
viz[*it]=1;
d[*it]=d[node]+1;
if(d[*it]>mare) mare=d[*it];
Q.push(*it);
}
}
}
}
int main()
{
f>>n;
for(int i=1;i<n;i++){
f>>x>>y;
G[x].push_back(y);
G[y].push_back(x);
}
for(int i=1;i<n;++i){
if(G[i].size()==1) BFS(i);
}
g<<mare+1<<'\n';
f.close();g.close();
return 0;
}