#include<algorithm>
#include<iostream>
#include<fstream>
#include<cstdio>
#include<cmath>
#include<cstring>
#include<vector>
#include<stack>
#define MAXN 10000
using namespace std;
int main()
{
	freopen("cowroute.in","r",stdin);
	freopen("cowroute.out","w",stdout);
	int n, b, e, i, j, k, now, way, min=999999;
	bool T1, T2;
	cin>>b>>e>>n;
	for(i=0;i<n;i++)
	{
		cin>>now>>way;
		T1=false;
		T2=false;
		for(j=0;j<way;j++)
		{
			cin>>k;
			if(k==b && T2!=true)
			{
				T1=true;
			}
			if(k==e)
			{
				T2=true;
			}
		}
		if(T1==true && T2==true)
		{
			if(min>now)
			{
				min=now;
			}
		}
	}
	if(min==999999)cout<<-1<<endl;
	else cout<<min<<endl;
	return 0;
}