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++: #define _CRT_SECURE_NO_WARNINGS // #pragma warning(disable:4996)
#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <vector>
#include <string>
#include <queue>
#include <functional>
#include <sstream>
#include <cmath>
#include <set>
#include <map>
#include <stack>
using namespace std; 

#define rep(i,a,b) for(int i=(a);i<(b);i++)
#define rrep(i,a,b) for(int i=(a);i>=(b);i--)
#define pb push_back
#define mp(a,b) make_pair(a,b)
#define all(a) a.begin(),a.end()
#define len(x) ((int)(x).size())
#define tmax(a,b,c) max((a),max((b),(c)))
#define tmin(a,b,c) min((a),min((b),(c)))
#define debug(x) cerr << #x << " is " << x << endl;

typedef pair<int, int> Pii;
typedef map<int, int> Mii;
typedef vector<int> Vi;
typedef long long ll;
const int inf = 2e9;
const ll ll_inf = 1e17;
const int mod = 1e9 + 7;
const long double eps = 1e-10;
 
int main()
{
	while(1) {
		int n, m, k;
		cin >> n;
		if (!n) break;
		set<int> p[101];
		rep(i,0,n) {
			cin >> m;
			rep(j,0,m) {
				int t; 
				cin >> t;
				if (t-1 != i) p[i].insert(t);
			}
		}
		Vi l;
		cin >> k;
		rep(i,0,k) {
			int t;
			cin >> t;
			l.pb(t);
		}

		
		Vi  f;
		rep(i,0,n) {
			bool f2 = true;
			rep(j,0,k) {
				auto it = lower_bound(all(p[i]),l[j]);
				if (it == p[i].end()) {
					f2 = false;
					break;
				}
			}
			if (f2) f.pb(i);
		}
		//cout << "answer is ";
		if (len(f) == 1) cout << f[0]+1 << endl;
		else cout << -1 << endl;
	}

	return 0;
}

C++: #include <iostream>
#include <vector>

using namespace std;


int main(){
  int n, m, k;
  bool flag, all_flag;
  vector< vector<int> > v;
  vector<int> leakage;
  vector<int> answer;
  while(true){
    cin >> n;
    if (n == 0)
    {
      break;
    }
    v.reserve(n);
    for (int i = 0; i < n; ++i)
    {
      cin >> m;
      v[i].reserve(m);
      for (int j = 0; j < m; ++j)
      {
        cin >> v[i][j];
      }
    }
    cin >> k;
    leakage.reserve(k);
    for (int i = 0; i < k; ++i)
    {
      cin >> leakage[i];
    }

    // cout << n << endl;
    for (int i = 0; i < n; ++i)
    {
      all_flag = true;
      for (int t = 0; t < k; ++t)
      {
        flag = false;
        for (int j = 0; j < sizeof(v[i]) / sizeof(v[i][0]); ++j)
        {
          if (v[i][j] == leakage[t])
          {
            flag = true;
            break;
          }
        }
        if (flag == false){
          all_flag = false;
          break;
        }
      }
      if (all_flag == true)
      {
        answer.push_back(i+1);
      }
    }
    if (answer.size() == 1){
      cout << answer[0] << endl;
    }else{
      cout << -1 << endl;
    }
    v.clear();
    leakage.clear();
    answer.clear();
  }
}

C++: #include<stdio.h>
#include<vector>
#include<algorithm>
#include<iterator>
using namespace std;
int main()
{
	int n,m,k,p;
	vector<int>known[100];
	vector<int>vk,va,vb;
	while(scanf("%d",&n),n)
	{
		int i,j;
		for(i=0;i<n;++i)
			known[i].clear();
		for(i=0;i<n;++i)
		{
			scanf("%d",&m);
			for(j=0;j<m;++j)
			{
				scanf("%d",&p);
				known[p-1].push_back(i);
			}
		}
		scanf("%d",&k);
		vk.clear();
		for(i=0;i<k;++i)
		{
			scanf("%d",&p);
			vk.push_back(p-1);
		}
		sort(vk.begin(),vk.end());
		va.clear();
		for(i=0;i<n;++i)
		{
			va.push_back(i);
			sort(known[i].begin(),known[i].end());
		}
		vector<int>*vp, *vq;
		vp=&va; vq=&vb;
		for(i=0;i<vk.size();++i)
		{
			vq->clear();
			set_intersection(vp->begin(),vp->end(),known[vk[i]].begin(),known[vk[i]].end(),back_inserter(*vq));
			swap(vp,vq);
		}
		printf("%d\n", vp->size()==1?vp->at(0)+1:-1);
	}
}

C++: #include<stdio.h>
int b[100][100];
int c[100];
int main(){
	int a;
	while(scanf("%d",&a),a){
		for(int i=0;i<100;i++){
			c[i]=1;
			for(int j=0;j<100;j++)b[i][j]=0;
		}
		for(int i=0;i<a;i++){
			int p;scanf("%d",&p);
			for(int j=0;j<p;j++){
				int q;
				scanf("%d",&q);q--;
				b[i][q]=1;
			}
		}
		int e;
		scanf("%d",&e);
		for(int i=0;i<e;i++){
			int f;
			scanf("%d",&f);f--;
			for(int j=0;j<a;j++)if(!b[j][f])c[j]=0;
		}
		int v=0;for(int i=0;i<a;i++)v+=c[i];
		if(v!=1)printf("-1\n");
		else{
			for(int i=0;i<a;i++)if(c[i])printf("%d\n",i+1);
		}
	}
}

C++: #include <bits/stdc++.h>
using namespace std;
template <typename T> using V = vector<T>;

bool solve() {
    int N;
    cin >> N;
    if(!N) return false;
    V<V<int>> P(N);
    for(auto &&v : P) {
        int m;
        cin >> m;
        V<int> tmp(m);
        for(auto &&e : tmp) {
            cin >> e;
            e--;
        }
        v = tmp;
    }

    int K;
    cin >> K;
    V<int> L(K);
    for(auto &&e : L) {
        cin >> e;
        e--;
    }

    V<int> ok;
    for(int i = 0; i < N; i++) {
        bool aint = true;
        for(int e : L) {
            bool found = false;
            for(int f : P[i]) {
                if(e == f) found = true;
            }
            if(!found) aint = false;
        }
        if(aint) ok.push_back(i);
    }

    if(ok.size() == 1) cout << ok[0] + 1;
    else cout << -1;
    cout << endl;
    return true;
}

int main() {
    while(solve());
    return 0;
}