#include <iostream>
#include <fstream>
#include <vector>
#include <algorithm>
#include <queue>

using namespace std;

ifstream fin("iepuri1.in");
ofstream fout("iepuri1.out");

const int MOD = 30011;
const int DIM = 105;

vector <int> G[DIM];

int n,k,Root,x,y,Nr[DIM],Dist[DIM];

void Read()
{
    fin>>n>>k;
    for(int i=1;i<=n-1;i++)
    {
        fin>>x>>y;
        G[x].push_back(y);
        Nr[y]++;
    }
}

void GetRoot()
{
    for(int i=1;i<=n;i++)
    {
        if(!Nr[i])
        {
            Root=i;
            break;
        }
    }
}

queue <int> Q;

void BFS(int node)
{
    Q.push(node);
    Dist[node]=1;
    while(!Q.empty)
    {
        int nod=Q.front();
        vector <int> ::iterator it;
        for(it=G[nod].begin();it!=G[nod].end();it++)
        {
            if(!Dist[*it])
            {
                Dist[*it]=Dist[node]+1;
                Q.push(*it);
            }
        }
        Q.pop();
    }
}

int main()
{
    Read();
    GetRoot();
    BFS(Root);

}