Go: package main

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

func main() {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)
	sc.Scan()
	num, _ := strconv.Atoi(sc.Text())
	nodes := make(map[int]*node)

	for i := 0; i < num; i++ {
		sc.Scan()
		id, _ := strconv.Atoi(sc.Text())
		sc.Scan()
		nodeNum, _ := strconv.Atoi(sc.Text())
		n := node{id, make([]int, 0), -1}
		for j := 0; j < nodeNum; j++ {
			sc.Scan()
			nid, _ := strconv.Atoi(sc.Text())
			n.nexts = append(n.nexts, nid)
		}
		nodes[id] = &n
	}
	nodes[1].depth = 0

	walk(1, 0, &nodes)
	for i := 1; i < len(nodes)+1; i++ {
		fmt.Printf("%v %v\n", (*nodes[i]).id, (*nodes[i]).depth)
	}
}

var time int
var record [100][100]bool
var q Queue

func walk(nid int, from int, nodes *map[int]*node) {
	q.Enqueue((*nodes)[nid])
	for !q.IsEmpty() {
		n := q.Dequeue().(*node)
		for _, v := range n.nexts {
			n2 := (*nodes)[v]
			if n2.depth != -1 {
				continue
			}
			n2.depth = n.depth + 1
			q.Enqueue((*nodes)[v])
		}
	}
}

type node struct {
	id    int
	nexts []int
	depth int
}

// Queue is Queue
type Queue struct {
	val []interface{}
}

// Enqueue value
func (queue *Queue) Enqueue(val interface{}) {
	queue.val = append(queue.val, val)
}

// Dequeue value
func (queue *Queue) Dequeue() interface{} {
	res := queue.val[0]
	queue.val = queue.val[1:len(queue.val)]
	return res
}

// IsEmpty return true when queue is empty
func (queue *Queue) IsEmpty() bool {
	return len(queue.val) == 0
}

C++: #include<iostream>
#include<queue>
using namespace std;
int N;
int D[101];
void bfs(int src){
    int u[101],k[101],a[10010],d[101][101];
    bool visit[101];
    for(int i=1;i<=N;++i){
        cin>>u[i]>>k[i];
        for(int j=0;j<k[i];++j){
            cin>>a[j];
            d[u[i]][a[j]]=1;
        }
        visit[i]=true;
    }
    queue<int>Q;
    Q.push(src);
    D[src]=0;
    visit[src]=false;
    while(!Q.empty()){
        int cur=Q.front();
        Q.pop();
        for(int i=1;i<=N;++i){
            if(d[cur][i]==1&&visit[i]){
                visit[cur]=false;
                visit[i]=false;
                D[i]=D[cur]+1;
                Q.push(i);
            }
        }
    }
    for(int i=1;i<=N;++i){
        if(i!=1&&D[i]==0){
            D[i]=-1;
        }
        cout<<i<<" "<<D[i]<<endl;
    }
}
int main(){
    cin>>N;
    int start=1;
    bfs(start);
}

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

int M[101][101], cond[101], d[101], n;

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

void bfs(int x)
{
	queue<int> Q;

	Q.push(x);
	cond[x] = -1;
	d[x] = 0;

	while (!Q.empty()) {
		int u = Q.front();
		for (int i = 1; i <= n; i++) {
			if (M[u][i] == 1 && cond[i] == 0) {
				Q.push(i);
				d[i] = d[u] + 1;				
				cond[i] = -1;
			}
		}
		Q.pop();
		cond[u] = 1;
	}
}

int main()
{
	ios::sync_with_stdio(false);
	cin.tie(0);

	cin >> n;
	setAdj();

	for (int i = 1; i <= n; i++)
		if (cond[i] == 0) bfs(i);

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

	return 0;
}

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

using namespace std;
static const int N=100;
static const int INFTY = (1<<21);

int n,Mtw[N][N];
int d[N];

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

int main(){
    int utw,ktw,vtw;

    cin >> n;
    for(int i=0;i<n;i++){
        for(int j=0;j<n;j++)Mtw[i][j]=0;
    }

    for(int i=0;i<n;i++){
        cin>>utw>>ktw;
        utw--;
        for(int j=0;j<ktw;j++){
            cin >> vtw;
            vtw--;
            Mtw[utw][vtw]=1;
        }
    }

    bfs(0);

    return 0;
}

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

using namespace std;
static const int N = 100;
static const int INFTY = (1 << 21);

int n, M[N][N];
int d[N];

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[u] != 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<queue>

using namespace std;
static const int N = 100;
static const int INFTY = (1<<21);

int n, M[N][N];
int d[N];

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;
  int i,j;

  cin >> n;
  for(i=0;i < n;i++)
    {
      for(j=0;j < n;j++)
        {
          M[i][j] = 0;
        }
    }

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

  bfs(0);

  return 0;

}