Go: package main

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
	"strings"
)

func main() {
	io := NewIo()
	defer io.Flush()

	for {
		N := io.NextInt()
		if N == 0 {
			break
		}
		set := make([]map[int]struct{}, N)
		for i := 0; i < N; i++ {
			set[i] = make(map[int]struct{})
			M := io.NextInt()
			for j := 0; j < M; j++ {
				p := io.NextInt()
				set[i][p] = struct{}{}
			}
		}
		K := io.NextInt()
		l := make([]int, K)
		for i := 0; i < K; i++ {
			l[i] = io.NextInt()
		}

		ans := 0
	FOR_OUTER:
		for i := 0; i < N; i++ {
			for j := 0; j < K; j++ {
				if _, f := set[i][l[j]]; f == false {
					continue FOR_OUTER
				}
			}
			switch ans {
			case 0:
				ans = i + 1
			default:
				ans = -1
			}
		}
		if ans > 0 {
			io.Println(ans)
		} else {
			io.Println(-1)
		}
	}
}

// I/O template
type Io struct {
	reader    *bufio.Reader
	writer    *bufio.Writer
	tokens    []string
	nextToken int
}

func NewIo() *Io {
	return &Io{
		reader: bufio.NewReader(os.Stdin),
		writer: bufio.NewWriter(os.Stdout),
	}
}

func (io *Io) Flush() {
	err := io.writer.Flush()
	if err != nil {
		panic(err)
	}
}

func (io *Io) NextLine() string {
	var buff []byte
	for {
		line, isPrefix, err := io.reader.ReadLine()
		if err != nil {
			panic(err)
		}
		buff = append(buff, line...)
		if !isPrefix {
			break
		}
	}
	return string(buff)
}

func (io *Io) Next() string {
	for io.nextToken >= len(io.tokens) {
		line := io.NextLine()
		io.tokens = strings.Fields(line)
		io.nextToken = 0
	}
	s := io.tokens[io.nextToken]
	io.nextToken++
	return s
}

func (io *Io) NextInt() int {
	i, err := strconv.Atoi(io.Next())
	if err != nil {
		panic(err)
	}
	return i
}

func (io *Io) NextFloat() float64 {
	i, err := strconv.ParseFloat(io.Next(), 64)
	if err != nil {
		panic(err)
	}
	return i
}

func (io *Io) Println(a ...interface{}) {
	fmt.Fprintln(io.writer, a...)
}

func (io *Io) Printf(format string, a ...interface{}) {
	fmt.Fprintf(io.writer, format, a...)
}

func (io *Io) PrintIntSlice(a []int) {
	b := []interface{}{}
	for _, x := range a {
		b = append(b, x)
	}
	io.Println(b...)
}

func (io *Io) PrintStringSlice(a []string) {
	b := []interface{}{}
	for _, x := range a {
		b = append(b, x)
	}
	io.Println(b...)
}

func Log(name string, value interface{}) {
	fmt.Fprintf(os.Stderr, "%s=%+v\n", name, value)
}

func ExampleIo() {
	io := NewIo()
	defer io.Flush()
	a := make([]int, 0, 3)
	a[0], a[1], a[2] = io.NextInt(), io.NextInt(), io.NextInt()
	io.Println(a)
	io.PrintIntSlice(a)
	Log("io", a)
}

C++: #include <bits/stdc++.h>
using namespace std;
#define int long long
#define ll long long
#define fi first
#define se second
#define pb push_back
#define rep(i, s, n) for (int i = s; i < n; i++)
#define rrep(i, s, n) for (int i = (n)-1; i >= (s); i--)
#define REP(i,n) for(int i = 0;i < n; i++)
#define all(a) a.begin(),a.end()
typedef pair<int,int>pint;
typedef vector<int>vint;
typedef vector<pint>vpint;
const long long MOD = 1000000007, INF = 1e18;

#define endl '\n'
#define IOS() ios_base::sync_with_stdio(0);cin.tie(0)
 
template<class T>inline bool chmax(T& a,T b){if(a<b){a=b;return true;}return false;}
template<class T>inline bool chmin(T& a,T b){if(a>b){a=b;return true;}return false;}
template<typename T>vector<T>
make_v(size_t a){return vector<T>(a);}
template<typename T,typename... Ts>
auto make_v(size_t a,Ts... ts){
	return vector<decltype(make_v<T>(ts...))>(a,make_v<T>(ts...));
}

template<typename T,typename V>
typename enable_if<is_class<T>::value==0>::type
fill_v(T &t,const V &v){t=v;}

template<typename T,typename V>
typename enable_if<is_class<T>::value!=0>::type
fill_v(T &t,const V &v){
	for(auto &e:t) fill_v(e,v);
}



signed main(){
	IOS();
	vector<int>ans;
	while(1){
		int N;
		cin>>N;
		if(!N)break;
		int a[N][N]={};
		rep(i,0,N){
			int t;
			cin>>t;
			rep(j,0,t){
				int tt;
				cin>>tt;
				tt--;
				a[i][tt]=1;
			}
		}
		int K;
		cin>>K;
		vector<int>l(K);
		rep(i,0,K){
			cin>>l[i];
			l[i]--;
		}
		int flg = -2;
		rep(i,0,N){
			int ok = 1;
			rep(j,0,K){
				if(!a[i][l[j]]){
					ok=0;
				}
			}
			if(ok){
				if(flg==-2)flg = i;
				else{
					flg = -2;
					break;
				}
			}
		}
		ans.push_back(flg);
	}
	for(auto e:ans){
		cout<<e+1<<endl;
	}
}

C++: #include<stdio.h>
#include<iostream>
using namespace std;

int main(){

int N;
while(1){
cin>>N;
int M;
bool n[103][103]={};
for(int i=1;i<=N;i++){
cin>>M;
for(int j=0;j<M;j++)
{int x;cin>>x;n[i][x]=true;}
}

bool R[101]={};
cin>>M;
for(int i=0;i<M;i++)
{int x;cin>>x;R[x]=true;}
int c=0,k=0;

for(int i=1;i<=N;i++){bool f=true;
for(int j=1;j<=N;j++)
{
if(n[i][j]!=R[j]&&R[j]==true)f=false;
}
if(f==true){c++;k=i;}
}

if(c==1)cout<<k<<endl;
else{cout<<"-1"<<endl;}
}
return 0;
}

C++: 
//http://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=2399

#include<iostream>
#include<map>
#include<vector>
#include<algorithm>
#include<cmath>
#include<climits>
#include<ctime>
#include<cstring>
#include<numeric>

#define ALL(v) (v).begin(),(v).end()
#define REP(i,p,n) for(int i=p;i<(int)(n);++i)
#define rep(i,n) REP(i,0,n)
#define dump(a) (cerr << #a << "=" << (a) << endl)
#define DUMP(list) cout << "{ "; for(auto nth : list){ cout << nth << " "; } cout << "}" << endl;

using namespace std;

class member
{
	private:
		int id;
		bool flag;
		vector<int> privacy_list;
	public:
		member(int ID):id(ID), flag(false){}

		void set_flag(bool FLAG){
			flag = FLAG;
		}

		bool get_flag(){
			return flag;
		}

		int get_id(){
			return id;
		}

		void add(int ID){
			privacy_list.push_back(ID);
		}

		bool check_list(int ID)
		{
			bool check=false;
			rep(i,privacy_list.size()){
				if(ID == privacy_list[i]){ check=true; }
			}
			return check;
		}

		void show()
		{
			dump(id);
			dump(flag);
			DUMP(privacy_list);
		}
};

int main()
{
	int N,M;
	while(cin >> N && N)
	{
		vector<member> members;

		rep(i,N)
		{
			members.push_back(member(i+1));
			cin >> M;

			int tmp;
			rep(j,M)
			{
				cin >> tmp;
				members[i].add(tmp);
			}
		}

		

		int K;
		cin >> K;
		vector<int> leak(K);
		rep(i,K){
			cin >> leak[i];
		}	
	
		rep(i,leak.size())
		{
			rep(j,N)
			{
				if(members[j].check_list(leak[i])){
					members[j].set_flag(true);
				}else{
					members[j].set_flag(false);
				}
			}
		}
	
		vector<int> ans;
		rep(i,members.size()){
			if(members[i].get_flag()){ans.push_back(members[i].get_id());}
		}

		if(ans.size() == 1){
			cout << ans[0] << endl;
		}else{
			cout << "-1" << endl;
		}
	}
	return 0;
}