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 <vector>
#include <stack>
#include <queue>

using namespace std;

static const int N = 100;
static const int WHITE = 0;
static const int GREY = 1;
static const int BLACK = 2;

int n, m[N][N];
bool visited[N];
int d[N], dist;


void bfs(int i){
	queue<int> q; q.push(i);
	visited[i] = true;

	while (!q.empty()) {
		int u = q.front(); q.pop();
		for (int v = 0; v < n; ++v) {
			if (!visited[v] && m[u][v]){
				d[v] = d[u] + 1;
				visited[v] = true;
				q.push(v);
			}
		}
	}
}


void search(){
	for (int i = 0; i < n; ++i) {
		d[i] = -1;
		visited[i] = false;
	}
	d[0] = 0;
	bfs(0);

	for (int i = 0; i < n; ++i)	cout << i + 1 << " " << d[i] << endl;
}


int main()
{
	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) {
		int u, d; cin >> u >> d;
		for (int j = 0; j < d; ++j) {
			int v; cin >> v;
			m[u - 1][v - 1] = 1;
		}
	}

	search();

	return 0;
}

C++: #include <iostream>
#include <queue>
static const int MAX = 100;
static const int INFTY = (1<<21);
using namespace std;

enum Color {
  WHITE, GRAY, BLACK
};

int n;
int G[MAX][MAX];
int d[MAX];
Color color[MAX];


void bfs_init() {
  for (int i = 0; i < n; i++) {
    color[i] = WHITE;
    d[i] = INFTY;
  }
}

void bfs(int r) {
  bfs_init();
  queue<int> q;
  q.push(r);
  d[r] = 0;
  int u;
  while (!q.empty()) {
    u = q.front();
    q.pop();
    for (int v = 0; v < n; v++) {
      if (G[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() {
  cin >> n;
  for (int i = 0; i < n; i++) {
    for (int j = 0; j < n; j++) {
      G[i][j] = 0;
    }
  }
  for (int i = 0; i < n; i++) {
    int vi, out_v_num;
    cin >> vi;
    cin >> out_v_num;
    for (int j = 0; j < out_v_num; j++) {
      int out_vi;
      cin >> out_vi;
      G[vi-1][out_vi-1] = 1;
    }
  }
  bfs_init();
  bfs(0);
  return 0;
}

C++: ///
// File:  alds1_11_c.cpp
// Author: ymiyamoto
//
// Created on Wed Oct 18 00:49:05 2017
//

#include <cstdint>
#include <iostream>
#include <queue>
#include <vector>

using namespace std;
static uint32_t graph[100][100];
static vector<int32_t> d(100, -1);
static queue<uint32_t> q;

static void bfs(uint32_t n)
{
  q.push(0);
  d[0] = 0;

  while (!q.empty()) {
    uint32_t index = q.front();
    q.pop();

    for (uint32_t i = 0; i < n; i++) {
      if (d[i] == -1 && graph[index][i] == 1) {
        q.push(i);
        d[i] = d[index] + 1;
      }
    }
  }
}

int32_t main()
{
  uint32_t n;
  cin >> n;

  for (uint32_t i = 0; i < n; i++) {
    uint32_t id, k;
    cin >> id >> k;
    for (uint32_t j = 0; j < k; j++) {
      uint32_t val;
      cin >> val;
      graph[id - 1][val - 1] = 1;
    }
  }

  bfs(n);

  for (uint32_t i = 0; i < n; i++) {
    cout << i + 1 << " " << d[i] << endl;
  }

  return 0;
}

C++: #include <iostream>
#include <queue>
using namespace std;
#define N (100)
#define INFINITY (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]=INFINITY;
    }
    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]!=INFINITY)continue;
            d[v]=d[u]+1;
            q.push(v);
        }
    }
    for(int i=0;i<n;i++){
        cout<<i+1<<" "<<((d[i]==INFINITY)?(-1):d[i])<<endl;
    }
}

int main(void){
    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 <bits/stdc++.h>
using namespace std;
using Graph = vector<vector<int>>;

int	main()
{
	int	n;
	cin >> n;
	Graph	graph(n);
	int	u;
	for (int i = 0; i < n; ++i) {
		int	k, v;
		cin >> u >> k;
		--u;
		for (int j = 0; j < k; ++j) {
			cin >> v;
			--v;
			graph.at(u).push_back(v);
		}
	}
	vector<int>	cost(n, -1);
	queue<int>	que;
	cost.at(0) = 0;
	que.push(0);
	int	cost_u;
	while (!que.empty()) {
		u = que.front();
		que.pop();
		cost_u = cost.at(u);
		for (int v : graph.at(u)) {
			if (cost.at(v) != -1) continue;
			cost.at(v) = cost_u + 1;
			que.push(v);
		}
	}
	for (int i = 0; i < n; ++i) {
		cout << i + 1 << " " << cost.at(i) << endl;
	}
}

C++: #include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
#include<climits>
#include<iostream>
#include<sstream>
#include<utility>
#include<map>
#include<vector>
#include<queue>
#include<algorithm>
#include<set>
#include<stack>

using namespace std;

const int MAX_N = 101;
const int DUMMY = 10000;

int N, u, k, v = 0;

vector<int>V [MAX_N];
int d [MAX_N];
bool visited [MAX_N];

bool bfs(int u, int depth)
{
    //if (V[u].size() == 0) return false;
    
    // for (int i = 0; i < V[u].size(); ++i)
    //     cout << V[u][i] << ' ';
    // cout << endl;
    
    for (int i = 0; i < V[u].size(); ++i)
        bfs(V[u][i] - 1, depth + 1);
    
    d[u] = min(d[u], depth);
    
    if (V[u].size() == 0 || u == 0)
        return true;
}

int main()
{
    //initialize
    for (int i = 0; i < MAX_N; ++i) {
        d[i]   = DUMMY;
        visited[i] = false;
    }
    
    //input
    scanf("%d", &N);
    for (int i = 0; i < N; ++i) {
      scanf("%d %d", &u, &k);
      for (int j = 0; j < k; ++j) {
          scanf("%d", &v);
          V[i].push_back(v);
      }
      sort(V[i].begin(), V[i].end());
    }

    //serach
    bfs(1-1, 0);
    
    //output
    for (int i = 0; i < N; ++i) {
      if(d[i] == DUMMY) cout << i+1 << ' ' << -1 << endl;
      else cout << i+1 << ' ' << d[i] << endl;
    }

    return 0;
}