Go: package main

/*
グラフの表現 隣接行列による表現
*/

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

func main() {
	scanner := makeScanner(8192)
	n := eGetInt(scanner)
	g := make([][]int, n+1)
	for i := 1; i < n+1; i++ {
		g[i] = make([]int, n+1)
		ints := eGetInts(scanner)
		num := ints[0]
		for j := 0; j < ints[1]; j++ {
			g[num][ints[j+2]] = 1
		}
	}
	dist := make([]int, n+1)
	for i := 0; i < len(dist); i++ {
		dist[i] = -1
	}
	q := []int{}

	// 訪問する
	q = append(q, 1)
	dist[1] = 0

	// キューが空でない限り
	for len(q) > 0 {
		// 先頭を取り出す
		top := 0
		top, q = q[0], q[1:]
		// 隣接マスを入れる.
		for i := 1; i < n+1; i++ {
			// 辺がある
			if g[top][i] == 1 {
				if dist[i] == -1 {
					// 訪問済みでなければ
					q = append(q, i)
					dist[i] = dist[top] + 1
				}
			}
		}
	}
	for i := 1; i < n+1; i++ {
		fmt.Println(i, dist[i])
	}
}

////////////////////////////////////////////////////////////////////////////////
// ライブラリ
////////////////////////////////////////////////////////////////////////////////
func makeScanner(maxByte int) *bufio.Scanner {
	scanner := bufio.NewScanner(os.Stdin)
	scanner.Buffer(make([]uint8, 0, 8192), maxByte)
	return scanner
}
func makeWordScanner() *bufio.Scanner {
	scanner := makeScanner(8192)
	scanner.Split(bufio.ScanWords)
	return scanner
}
func eGetLine(r *bufio.Scanner) string {
	if r.Scan() {
		return r.Text()
	}
	err := r.Err()
	if err != nil {
		log.Fatal(err)
	}
	// EOF
	return ""
}
func eGetInt(r *bufio.Scanner) int {
	line := eGetLine(r)
	return eAtoi(line)
}
func eGetInt64(r *bufio.Scanner) int64 {
	line := eGetLine(r)
	return eAtoInt64(line)
}
func eGetFields(r *bufio.Scanner) []string {
	line := eGetLine(r)
	return strings.Fields(line)
}
func eGetInts(r *bufio.Scanner) []int {
	fields := eGetFields(r)
	ints := make([]int, len(fields))
	for i := 0; i < len(ints); i++ {
		ints[i] = eAtoi(fields[i])
	}
	return ints
}
func eGetInt64s(r *bufio.Scanner) []int64 {
	fields := eGetFields(r)
	ints := make([]int64, len(fields))
	for i := 0; i < len(ints); i++ {
		ints[i] = eAtoInt64(fields[i])
	}
	return ints
}
func eGetChars(r *bufio.Scanner) []string {
	line := eGetLine(r)
	return strings.Split(line, "")
}
func eAtoi(s string) int {
	n, err := strconv.Atoi(s)
	if err != nil {
		log.Fatal(err)
	}
	return n
}
func eAtoInt64(s string) int64 {
	n, err := strconv.ParseInt(s, 10, 64)
	if err != nil {
		log.Fatal(err)
	}
	return n
}

C++: #include<iostream>
#include<vector>
#include<queue>
using namespace std;
int n;
int D[100];
int matrix[100][100];
void bfs(int src)
{
    cerr<<"bfs root = "<<src<<endl;
    queue<int> q;
    q.push(src);
    D[src]=0;
    while(!q.empty())
    {
        int cur=q.front();
        q.pop();
        cerr<<"visiting "<<cur<<' '<<D[cur]<<endl;
        for(int dst=0;dst<n;dst++)
        {
            if(matrix[cur][dst]==1&&D[dst]==99999999)
            {
                D[dst]=D[cur]+1;
                q.push(dst);
            }
        }
    }
};

int main()
{
    vector<int> l[101];
    cin>>n;
    for(int i=0;i<n;i++)
    {
        int u,k;
        cin>>u>>k;
        for(int j=0;j<k;j++)
        {
            int tmp;
            cin>>tmp;
            l[u].push_back(tmp);
        }
    }
    
    for(int i=0;i<100;i++)
    {
        D[i]=99999999;
    }
    
    for(int i=0;i<n;i++)
    {
        for(int j=0;j<n;j++)
        {
            matrix[i][j]=0;
        }
    }
    
    for(int i=1;i<n+1;i++)
    {
        for(int j=0;j<l[i].size();j++)
        {
            matrix[i-1][l[i][j]-1]=1;
        }
    }
    
    for(int i=0;i<n;i++)
    {
        bfs(i);
    }
    
    for(int i=0;i<n;i++)
    {
        cout<<(i+1)<<' '<<D[i]<<endl;
    }
}

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

using namespace std;

#define MAX 110
int num;
int matrix[MAX][MAX];
int dst[MAX];

void input(){
    for(int i=0;i<MAX;i++){
        dst[i] = -1;
        for(int j=0;j<MAX;j++){
            matrix[i][j] = 0;
        }
    }
    for(int i=1;i<=num;i++){
        int v; cin >> v;
        int tmp; cin >>tmp;
        for(int j=0;j<tmp;j++){
            int vi; cin >> vi;
            matrix[v-1][vi-1] = 1;
        }
    }
}

void bfs(){
    queue<int> Q;
    Q.push(0);
    dst[0] = 0;
    while(Q.size() != 0){
        int cur = Q.front();
        for(int i=0;i<num;i++){
            if(matrix[cur][i]==1){
                if(dst[i]==-1){
                    Q.push(i);
                    dst[i] = dst[cur] + 1;
                }
            }
        }
        Q.pop();
    }
    for(int i=0;i<num;i++){
        cout << i+1 << " " <<  dst[i] << endl;
    }
}

int main(){
    cin >> num;
    input();
    bfs();
}

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

using namespace std;

int main()
{
  bool firstFlag = true;
  int N, u, k, v, frontNum, ansNum;
  int depth = 0;

  cin >> N;
  vector<vector<int> > G(N, vector<int>(N, 0));
  vector<int> ansList(N, -1);
  queue<int> q, r;

  for (int i = 0; i < N; i++){
    cin >> u >> k;
    for (int j = 0; j < k; j++){
      cin >> v;
      G[u - 1][v - 1] = 1;
    }
  }
  q.push(0);
  ansList[0] = 0;
  while(!q.empty()){
    frontNum = q.front();
    q.pop();
    for (int i = 0; i < N;i++){
      if(G[frontNum][i] == 0)continue;
      if(ansList[i] != -1)continue;
      ansList[i] = ansList[frontNum] + 1;
      q.push(i);
    }
  }
  for (int i = 0; i < ansList.size();i++){
    cout << i + 1 << " " << ansList[i] << endl;
  }
  return 0;
}

C++: #include "bits/stdc++.h"
using namespace std;
static const int N=100;
static const int INFTY =(1<<21);

int n,M[N][N];
int d[N];//?????¢??§?¨??????¶???(color)???????????????

void bfs(int s){
	queue<int> q;
	q.push(s);
	for (int i = 0; i < n; ++i) {d[i]=INFTY;	}
	d[s]=0;
	int u;
	while(!q.empty()){
		u=q.front();q.pop();
		for (int v = 0; v < n; ++v) {
			if(M[u][v]==0)continue;
			if(d[v]!=INFTY)continue;
			d[v]=d[u]+1;
			q.push(v);
		}
	}
	for (int i = 0; i < n; ++i) {
		cout<<i+1<<" "<<((d[i]==INFTY)?(-1):d[i])<<endl;
	}
}

int main(){
	int u,k,v;
	cin>>n;
	for (int i = 0; i < n; ++i) {
		for (int j = 0; j < n; ++j) {
			M[i][j]=0;
		}
	}
	for (int i = 0; i < n; ++i) {
		cin>>u>>k;
		u--;
		for (int j = 0; j < k; ++j) {
			cin>>v;
			v--;
			M[u][v]=1;
		}
	}
	bfs(0);
	return 0;
}

C++: #include <iostream>
#include <stack>
#define NIL -1
#define N 110

using namespace std;

bool A[N + 1][N + 1];
int d[N + 1];
int n;

stack<int> s1;
stack<int> s2;

void bfs(int depth, stack<int> si, stack<int> so) {
  if (si.empty()) return;
  while (!si.empty()) {
    int u = si.top();
    si.pop();
    for (int v = 1; v <= n; v++) {
      if (A[u][v] && d[v] == NIL) {
        so.push(v);
        d[v] = depth;
      }
    }
  }
  bfs(depth + 1, so, si);
}

int main() {

  cin >> n;
  for (int i = 1; i <= n; i++) {
    for (int j = 1; j <= n; j++) {
      A[i][j] = false;
    }
  }

  for (int i = 1; i <= n; i++) {
    int u, k, v;
    cin >> u >> k;
    for (int j = 1; j <= k; j++) {
      cin >> v;
      A[u][v] = true;
    }
  }

  for (int i = 1; i <= N; i++) d[i] = NIL;
  s1.push(1);
  d[1] = 0;
  bfs(1, s1, s2);

  for (int i = 1; i <= n; i++) {
    cout << i << " " << d[i] << endl;
  }
}

C++: #include<bits/stdc++.h>
using namespace std;
#define rep(i,n) for(int i = 0; i < (n) ; i++)
constexpr auto INF = 2147483647;
typedef long long ll;

int main(){

  int n;
  cin >> n;
  int score[101];
  bool adjacent_graph[101][101];
  rep(i,101){
    score[i] = -1;
    rep(j,101) adjacent_graph[i][j] = false;
    }

  int vertex,edge,direction;
  rep(i,n){
    cin >> vertex >> edge;
    rep(j,edge){
      cin >> direction;
      adjacent_graph[vertex][direction]  = true;
      // adjacent_graph[direction][vertex]  = true;
    }
  }
  queue<int> que;
  que.push(1);
  score[1] = 0;
  while(!que.empty()){
    int now = que.front();que.pop();
    rep(i,n+1) {
      if(adjacent_graph[now][i] && score[i] == -1){
        score[i] = score[now]+1;
        que.emplace(i);
      }
    }
  }

  rep(i,n) cout  << i+1 << " " << score[i+1] << endl;

  return 0;
}