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++: /**
 * Bredth first search.
 * graphs could be circular.
 */

#include <iostream>
using namespace std;
const int N = 101;
int adj[N][N] = {0};
int d[N] = {0};

void bfs(int n, int dd) {
	if (d[n] != -1) return;
	d[n] = dd++;
	int k = adj[n][0];
	for (int j=1;j<=k;j++) {
		bfs(adj[n][j], dd);
	}
}

int main()
{
	int n;
	cin >> n;
	for (int i=1;i<=n;i++){
		int j, k;
		cin >> j >> k;
		d[j]=-1;
		adj[j][0]=k;
		for (int m=1;m<=k;m++) {
			int a;
			cin >> a;
			adj[j][m]=a;
		}
	}

	bfs(1, 0);

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

	return 0;
}

C++: #include <bits/stdc++.h>

#define NIL -1
#define INF 1000000001

using namespace std;
void bfs(const vector<vector<int> > &adj, vector<int> &d, queue<int> node_visit){
    int current_node;
    while(!node_visit.empty()){
        current_node = node_visit.front();
        node_visit.pop();
        for(int i = 1;i < d.size();i++){
            if(adj[current_node][i] == 1 && d[i] == -1){
                d[i] = d[current_node]+1;
                node_visit.push(i);
            }
        }
    }
    
}
int main(){
    int num_node;
    int node_ind,node_deg,adj_node;
    scanf("%d",&num_node);

    vector<vector<int> > adj(num_node+1,vector<int>(num_node+1,0));
    queue<int> node_visit;
    vector<int> d(num_node+1,NIL);

    for(int i = 0; i < num_node;i++ ){
        scanf("%d %d",&node_ind,&node_deg);
        for(int j = 0;j < node_deg;j++){
            scanf("%d",&adj_node);
            adj[node_ind][adj_node] = 1;
        }
    }
   
    node_visit.push(1);
    d[1] = 0;
    bfs(adj,d,node_visit);
    for(int i = 1; i < num_node+1;i++){
        printf("%d %d\n",i,d[i]);
    }

    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]; 
/* d[N] are distances which describe the state whether the node is already visited.
   if the value == INFTY, the edge is NOT yet visited.
 */

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--; // because the index is 0-origin!
        for (int j = 0; j < k; j++) {
            cin >> v;
            v--; // because the index is 0-origin!
            M[u][v] = 1; // edges between u and v are available (connected).
        }
    }
    
    bfs(0);
    
    return 0;
}

C++: #include <iostream>
#include <vector>
#include <queue>
using namespace std;
static const int MAX=101;

vector<int> Adjacency[MAX];
int dt[MAX];
bool Visited[MAX];

void bfs(int i)
{
    queue<int> Q;
    dt[i]=0;Q.push(i);
    Visited[i]=true;
    int d=0;
    while(!Q.empty())
    {
        int p=Q.front();Q.pop();d=dt[p]+1; //important
        for(int j=0;j<Adjacency[p].size();j++)
        {
            if(Visited[Adjacency[p][j]]==true) continue;
            //else
            Q.push(Adjacency[p][j]); Visited[Adjacency[p][j]]=true;
            dt[Adjacency[p][j]]=d;
        }
    }
}
int main()
{
    int n;
    cin>>n;
    for(int i=1;i<=n;i++)
    {
        int j,num;
        cin>>j>>num;
        for(int k=0;k<num;k++)
        {
            int t;cin>>t;
            Adjacency[j].push_back(t);
        }
    }
    bfs(1);
    for(int i=1;i<=n;i++)
    {
        cout<<i<<' '<<dt[i]<<endl;
    }
}