Go: package main

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

type AdjacentList struct {
	matrix [][]int
}

func NewEmptyAdjacentList(dim int) *AdjacentList {
	matrix := make([][]int, dim)
	for i := 0; i < dim; i++ {
		matrix[i] = make([]int, dim)
	}
	return &AdjacentList{matrix: matrix}
}

func (al *AdjacentList) set(node int, adjacent int) {
	al.matrix[node-1][adjacent-1] = 1
}

func (al *AdjacentList) findAdjacentsFor(node int) []int {
	adjacents := []int{}
	for i, v := range al.matrix[node-1] {
		if v == 1 {
			adjacents = append(adjacents, i+1)
		}
	}
	return adjacents
}

type DistanceList struct {
	list []int
}

func NewDistanceList(dim int) *DistanceList {
	list := make([]int, dim)
	for i := 0; i < dim; i++ {
		list[i] = -1
	}
	return &DistanceList{list: list}
}

func (dl *DistanceList) set(node int, distance int) {
	dl.list[node-1] = distance
}

func (dl *DistanceList) get(node int) int {
	return dl.list[node-1]
}

func (dl *DistanceList) isVisited(node int) bool {
	return dl.list[node-1] >= 0
}

type Position struct {
	node     int
	distance int
}

func main() {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)

	dim, err := nextInt(sc)
	if err != nil {
		panic(err)
	}

	al := NewEmptyAdjacentList(dim)

	for i := 1; i <= dim; i++ {
		node, err := nextInt(sc)
		if err != nil {
			panic(err)
		}

		adjacentNum, err := nextInt(sc)
		if err != nil {
			panic(err)
		}
		for j := 0; j < adjacentNum; j++ {
			adjacent, err := nextInt(sc)
			if err != nil {
				panic(err)
			}
			al.set(node, adjacent)
		}
	}

	dl := NewDistanceList(dim)

	bfs(al, dl)

	for i := 1; i <= dim; i++ {
		fmt.Printf("%d %d\n", i, dl.get(i))
	}
}

func bfs(al *AdjacentList, dl *DistanceList) {
	stack := []Position{Position{node: 1, distance: 0}}
	for len(stack) > 0 {
		currentPosition := stack[0]
		stack = stack[1:]
		if !dl.isVisited(currentPosition.node) {
			dl.set(currentPosition.node, currentPosition.distance)
		}
		for _, v := range al.findAdjacentsFor(currentPosition.node) {
			if !dl.isVisited(v) {
				stack = append(stack, Position{node: v, distance: currentPosition.distance + 1})
			}
		}
	}
}

func nextInt(sc *bufio.Scanner) (int, error) {
	sc.Scan()
	return strconv.Atoi(sc.Text())
}

C++: //ALDS1_11C
#include <iostream>
#include <vector>
#include <queue>
using namespace std;

static const int N=100;
static const int INF=(1<<21);
int n,d[N];
vector<vector<int> > M(N,vector<int>(N));

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

int main(){
 int u,k,v;
 cin>>n;
 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>
#define N 100
#define INFTY (1<<21)
using namespace std;

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 <stdio.h>
#include <queue>

using namespace std;
#define N 100
#define INF 2000000

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

void bfs(int s){
	int i,u,v;

	queue<int> q;
	q.push(s);
	for(i=0;i<n;i++){
		d[i] = INF;
	}

	d[s] = 0;

	while(!q.empty()){
		u = q.front();
		q.pop();
		for(v=0;v<n;v++){
			if(M[u][v] == 0) continue;
			if(d[v] != INF) continue;
			d[v] = d[u] + 1;
			q.push(v);
		}
	}
	for(i=0;i<n;i++){
		if(d[i] == INF){
			printf("%d -1\n",i+1);
		}else{
			printf("%d %d\n",i+1,d[i]);
		}
	}
}


int main(void){
	int i,j,u,k,v;

	scanf("%d",&n);

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

	for(i=0;i<n;i++){
		scanf("%d%d",&u,&k);
		u--;
		for(j=0;j<k;j++){
			scanf("%d",&v);
			v--;
			M[u][v] = 1;
		}
	}

	bfs(0);

	return 0;
}

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

using namespace std;

int D[100100];//始点からの距離を入れる
int g[1001][1001]={{0}};//要素を0で初期化
void bfs(int src,int n){//srcは開始位置この場合だと頂点1だから0
  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(g[cur][dst]==1 && D[dst]==0){
        D[dst]=D[cur]+1;
        Q.push(dst);
      }
    }
  }
}
void ans(int n){
  for (int i = 0; i < n; ++i)
  {
    cout << i+1 <<" "<<D[i]<<endl;
  }

}

int main(){
  // int g[1001][1001]={{0}};//要素を0で初期化
  int n,a,b,c;
  cin >> n;
  for (int i = 0; i < n; ++i)
  {
    cin >> a >> b ;
    for (int i = 0; i < b; ++i)
    {
      cin >> c;
      g[a-1][c-1]=1;/* code */
    }
  }
  bfs(0,n);
  ans(n);
  // for (int i = 0; i < n; ++i)
  // {
  //    for (int j = 0; j < n; ++j)
  //    {
  //     if (j==n-1)
  //     {
  //       cout << g[i][j] << endl;
  //     }else{
  //       cout << g[i][j] <<" ";
  //     }
  //    }
  // }


}