#include <fstream>
#include <iostream>
using namespace std;

int been[101];
bool adj[101][101];

void dfs(int v,int l)
{
	if (been[v])
	{
		fout<<l<<endl;
		return;
	}
	been[v] = 1;
	for (int i=1;i<=100;i++)
		if (adj[v][i])
			dfs(i,l+1);
}


int main()
{
	ifstream fin("DATA5.txt");
	ofstream fout("OUT5.txt");
	int times = 5;
	while (times--)
	{
		int n;
		fin>>n;
		memset(adj,0,sizeof adj);
		int i;
		for (i=0;i<n;i++)
		{
			int x,y;
			fin>>x>>y;
			adj[x][y]=1;
		}
		memset(been,0,sizeof been);
		dfs(1,0);

	}
	fin.close();
	fout.close();
	return 0;
}