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 <vector>
#include <iostream>
#define REP(i,n) for(int i = 0;i<(n);i++)
using namespace std;

int main(){
	int N;
	while(cin>>N,N){
		vector<vector<int> > p(N);
		REP(i,N){
			int m;
			cin >> m;
			p[i].resize(m);
			REP(j,m)cin >> p[i][j];
		}
		int k;
		cin >> k;
		vector<int> l(k);
		REP(i,k)cin >> l[i];
		int ct;
		bool is_find = false;
		int num_find = 0;
		REP(i,N){
			ct = 0;
			REP(j,p[i].size()){
				REP(a,k){
					if(ct == k)break;
					if(l[a] == p[i][j]){
						ct++;
						break;
					}
				}
			}
			if(ct == k ){
				if(!is_find){
					is_find = true;
					num_find = i+1;
				}else{
					is_find = false;
					break;
				}
			}
		}
		if(is_find)cout << num_find << endl;
		else cout << -1 << endl;
	}
}

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

int main(){
  
  int n, m, p, k, l[100], c, cnt, ans;
  bool f[100][100]={};

  while(cin>>n, n){
    for(int i=0;i<n;i++){
      cin>>m;
      for(int j=0;j<m;j++){
	cin>>p;
	f[i][p-1]=true;
      }
    }
    cin>>k;
    cnt=0;
    for(int j=0;j<k;j++) cin>>l[j];
    for(int j=0;j<n;j++){
      c=0;
      for(int x=0;x<k;x++){
	if(f[j][l[x]-1]) c++;
      }
      if(c==k){
	cnt++;
	if(cnt==1) ans=j;
      }
    }
    if(cnt==1) cout<<ans+1<<endl;
    else cout<<-1<<endl;
  }
  
  return 0;
}

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

using std::cin;
using std::cout;
using std::endl;
using std::vector;

int main(void) {
	while (1) {
		int member_num;
		cin >> member_num;
		if (member_num == 0) {
			break;
		}

		vector<vector<int>> member_info;
		for (int i = 0; i < member_num; i++) {
			vector<int> info;
			int info_num;
			cin >> info_num;
			for (int j = 0; j < info_num; j++) {
				int tmp;
				cin >> tmp;
				info.push_back(tmp);
			}
			member_info.push_back(info);
		}

		int leak_num;
		cin >> leak_num;
		vector<int> leak;
		for (int i = 0; i < leak_num; i++) {
			int tmp;
			cin >> tmp;
			leak.push_back(tmp);
		}

		vector<bool> flag(member_num, true);
		int flag_num = member_num;
		for (auto leak_itr = leak.begin(); leak_itr != leak.end(); ++leak_itr) {
			for (int i = 0; i < member_num; i++) {
				if (!flag[i]) {
					continue;
				}

				bool hit = false;
				for (auto info_itr = member_info[i].begin(); info_itr != member_info[i].end(); ++info_itr) {
					if (*info_itr == *leak_itr) {
						hit = true;
						break;
					}
				}
				if (hit == false) {
					flag[i] = false;
					flag_num--;
				}
			}
		}

		if (flag_num != 1) {
			cout << -1 << endl;
		} else {
			for (int i = 0; i < member_num; i++) {
				if (flag[i]) {
					cout << i + 1 << endl;
					break;
				}
			}
		}
	}
	return 0;
}

C++: #include<iostream>
#include<cstdio>
#include<string>
#include<algorithm>
#include<vector>

using namespace std;

int main(void){
	
	int n,m;
	
	while(cin >> n,n){
		vector<int>v[101];
		for(int i=1;i<=n;i++){
			cin >> m;
			int a;
			for(int j=0;j<m;j++){
				cin >> a;
				v[i].push_back(a);
			}
		}
		int k;
		cin >> k;
		vector<int>l(k);
		for(int i=0;i<k;i++)cin >> l[i];
		
		int ans=0,id=0;
		for(int i=1;i<=n;i++){
			bool fg=true;
			for(int j=0;j<l.size();j++)
				if(!binary_search(v[i].begin(),v[i].end(),l[j]))fg=false;
			if(fg)ans++,id=i;
		}
		if(ans==1)cout << id << endl;
		else cout << -1 << endl;
	}
	return 0;
}

C++: #include <iostream>
#include <vector>
using namespace std;
int main() {
  int N, M, p, K, t, ans;
  while (cin >> N, N) {
    vector< vector<int> > V(N);
    vector<int> A(N, 0);
    for (int i = 0; i < N; ++i) {
      cin >> M;
      for (int j = 0; j < M; ++j) {
	cin >> p;
	V[p-1].push_back(i);
      }
    }
    cin >> K;
    for (int i = 0; i < K; ++i) {
      cin >> p;
      for (int j = 0; j < V[p-1].size(); ++j) {
	++A[V[p-1][j]];
      }
    }
    t = 0;
    ans = -1;
    for (int i = 0; i < N; ++i) {
      if (A[i] == K) {
	++t;
	ans = i+1;
      }
    }
    if (t == 1) cout << ans << endl;
    else cout << -1 << endl;
  }
  return 0;
}

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

using namespace std;

int main(){
    while(true){
        int n;
        cin >> n;
        if(n==0)break;
        vector<vector<int> >list(n,vector<int>(n+1,0));
        for(int i=0;i<n;i++){
            cin >> list[i][0];
            for(int j=1;j<=list[i][0];j++){
                cin >> list[i][j];
            }
        }
        int k;
        cin >>k;
        vector<int> a(k,0);
        for(int i=0;i<k;i++){
            cin >> a[i];
            }
        bool flag=false;
        int ans=-1;
        for(int i=0;i<n;i++){
            for(int j=0;j<k;j++){
                flag=false;
                for(int l=1;l<=list[i][0];l++){
                    if(list[i][l]==a[j]){
                        flag=true;
                        break;
                    }
                }
            }
            if(flag){
               if(ans!=-1)ans=-1;
               else ans=i+1;
            }
        }
        cout << ans << endl;
    }
    return 0;
}