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 <stdio.h>
#include <iostream>
#include <queue>
using namespace std;

#define NODE_NUM 100

queue<int> que;

class Node
{
private:
	int next_num;
	int next_node_list[NODE_NUM];
public:
	Node();
	void AddNextNode(int id);
	bool Search(int id);
	int dist;
};

Node::Node()
{
	next_num = 0;
}

void Node::AddNextNode(int id)
{
	next_node_list[next_num] = id;
	next_num++;
}

Node Node_list[NODE_NUM + 1];

bool Node::Search(int id)
{
	for (int k = 0; k < next_num; k++) {
		if (Node_list[next_node_list[k]].dist == -1) {
			Node_list[next_node_list[k]].dist = dist + 1;
		}
	}

	for (int i = 0; i < next_num; i++) {
		if (next_node_list[i] == id) return true;
	}
	
	for (int j = 0; j < next_num; j++) {
		que.push(next_node_list[j]);
	}
	
	return false;
}

int main(void)
{
	//input
	int n;
	cin >> n;
	for (int i = 0; i < n; i++) {
		int u, k;
		cin >> u;
		cin >> k;
		Node_list[u] = Node();
		for (int j = 0; j < k; j++) {
			int v;
			cin >> v;
			Node_list[u].AddNextNode(v);
		}
	}
	
	//dist
	for (int k = 1; k <= n; k++) {
		Node_list[k].dist = -1;
	}

	Node_list[1].dist = 0;
	for (int i = 2; i <= n; i++) {
		bool ret = Node_list[1].Search(i);
		if (ret) continue;
		if (que.empty()) continue;
		do {
			ret = Node_list[que.front()].Search(i);
			que.pop();
		} while (!ret);
		while (!que.empty()) {
			que.pop();
		}
	}

	//output
	for (int i = 1; i <= n; i++) {
		cout << i << " " << Node_list[i].dist << "\n";
	}
	
	return 0;
}

C++: #include<iostream>
#include<queue>
#include<vector>
#define INF (int)1e9 + 7
using namespace std;
int n;
vector<pair<int, int> > adj[10000];
void dijkstra();
int main() {
    cin >> n;
    for (int i = 0; i < n; i++) {
        int u, k;
        cin >> u >> k;
        for (int j = 0; j < k; j++) {
            int v; //vertex cost
            cin >> v;
            adj[u].push_back(make_pair(1, v));
        }
    }
    dijkstra();
    return 0;
}
void dijkstra() {
    int dist[n + 1];
    dist[1] = 0;
    for (int i = 2; i <= n; i++) {
        dist[i] = INF;
    }
    priority_queue<pair<int, int> > q;
    q.push(make_pair(0, 1));
    while (!q.empty()) {
        int u = q.top().second;
        //int co = -q.top().first;
        q.pop();
        for (int i = 0; i < adj[u].size(); i++) {
            int v = adj[u][i].second; //adj[u]のi番目の番号
            int co2 = adj[u][i].first;
            if (dist[u] + co2 < dist[v]) {
                dist[v] = co2 + dist[u];
                q.push(make_pair(-dist[v] ,v));
            }
        }
    }
    for (int i = 1; i <= n; i++) {
        cout << i << " ";
        if (dist[i] == (int)1e9 + 7) {
            cout << -1 << endl;
        } else {
            cout << dist[i] << endl;
        }
    }
}

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;

    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 <vector>
using namespace std;
 
static const  int N =  100;
static const  int no =  -1;
 
int graph[N][N] = {{}};
int d[N] = {};
int n;
 
void bfs(int v){
  vector<int> V;
  V.push_back(v);
  int u;
    for(int i = 1;i <= n; i++){
      d[i] = no;
     
}
  d[v] = 0;
 
  while(!V.empty()){
    u = V.front();
    V.erase(V.begin());
 
    for(int i = 1;i <= n; i++){
      if(graph[u][i] == 0) continue;
      if(d[i] != no) continue;
      d[i] = d[u] +1;
      V.push_back(i);
    }
  }
}
 
 
int main(){
  int u,v,k;
  cin >> n ;
 
  for(int i = 0; i < n; i++){
    cin >> u >> k ;
    for(int j = 0; j < k ; j++){
      cin >> v;
      graph[u][v] = 1;
    }
  }
 
 
  bfs(1);
 
  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,m[N][N];
int d[N];

void bfs(int s){
    queue<int> q;
    q.push(s);
    int i;
    for(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(i=0;i<n;i++){
        cout << i+1 << " " << ((d[i]==INFTY)?(-1):d[i]) << endl;
    }
}

int main(){
    int u,k,v,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;
}