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++: #include<iostream>
#include<cstdio>
#define N 101
using namespace std;

typedef struct{
  int q[10000];
  int head;
  int tail;
}Queue;

//queue
Queue que;
int g[N][N]; 
int n;
int d[N];
bool us[N];
void Enque(int data){
  que.q[que.tail]=data;
  que.tail++;
}

int Deque(void){
  int data;
  data=que.q[que.head];
  que.head++;
  return data;
}

bool isEmpty(){
  if(que.tail-que.head==0)return true;
  else return false;
}

//bfs
void bfs(int s){
  int u,v;
  Enque(s);
  while(true){

    if(isEmpty()==true) {
      break;
    }
    u=Deque();
    //  cout << "u = " << u << endl;
      for(int i=1;i<= n;i++){
 
      if(us[i]==false && g[u][i] == 1){
	v=i;
	//	cout << "i - " << i <<endl;
	us[i]=true;
	d[v]=d[u]+1;
	Enque(v);
      }
    }
  }
}

int main(){

  int n2,data,u;

 //load n
  cin >>n;

  //initialize
  que.tail=0;
  que.head=0;
  for(int i=0;i<N;i++){
    us[i]=false;
    d[i]=-1;
    for(int j=0;j<N;j++){
      g[i][j]=0;
    }
  }

  //load data
  for(int i=0;i<n;i++){
    scanf("%d%d",&u,&n2);
    for(int j=0;j<n2;j++){
      scanf("%d",&data);
      g[u][data]=1;
    }
  }
  //execute

  d[1]=0;
  us[1]=true;
  bfs(1);


  //print
  for(int i=1;i<=n;i++){
    printf("%d %d\n",i,d[i]); 
  }

  return 0;
}

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

#define MAX_NODE 100
#define INF 1000000000

using namespace std;

int d[MAX_NODE];
vector<int> adj[MAX_NODE];

void bfs(int n, int start) {
	queue<int> que;

	for (int i = 0; i < n; i++)
		d[i] = (i == start ? 0 : INF);

	que.push(start);
	while(!que.empty()) {
		int from = que.front();
		que.pop();

		for (int i = 0; i < adj[from].size(); i++) {
			int to = adj[from][i];
			if (d[to] == INF) {
				d[to] = d[from] + 1;
				que.push(to);
			}
		}
	}
}

int main() {
	int n;

	cin >> n;

	for (int i = 0; i < n; i++) {
		int u, k;
		cin >> u >> k;
		u--;
		while (k--) {
			int v;
			cin >> v;
			v--;
			adj[u].push_back(v);
		}
	}

	bfs(n, 0);

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

	return 0;
}

C++: #include<iostream>
#include<cstdio>
#include<cstdlib>
#include<string.h>
#include<stack>
#include<queue>
using namespace std;

int n;
int m[100][100], d[100], f[100];
int t = 0;
char c[100];
queue<int> q;

void bfs(int u){
  q.push(u);
  c[u] = 'g';
  d[u] = 0;

  while(q.empty() == 0){
    u = q.front();
    q.pop();
    for(int i = 0; i < n; i++){
      if(m[u][i] == 1 && c[i] == 'w'){
        q.push(i);
        c[i] = 'g';
        d[i] = d[u] + 1;
      }

    }
    c[u] = 'b';
  }

}


int main(){

  cin >> n;

  for(int i = 0; i < n; i++){
    c[i] = 'w';
    d[i] = 100;
    for(int j = 0; j < n; j++){
      m[i][j] = 0;

    }
  }

  for(int i = 0; i < n; i++){
    int id, k, x;
    cin >> id >> k;
    for(int j = 0; j < k; j++){
      cin >> x;
      m[i][x - 1] = 1;
    }
  }

  bfs(0);

  for(int i = 0; i < n; i++){
    cout << i + 1 << " " <<((c[i] == 'w') ? -1 : d[i]) << endl;
  }

  return 0;
}

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

const int Max = 100;
const int white = 0;
const int black = 1;
int M[Max][Max];
int d[Max], nt[Max], color[Max];
int n;
queue<int> Q;

int next(int u){
    for(int v=nt[u]; v<n; v++){
        nt[u] = v + 1;
        if(M[u][v]) return v;
    }
    return -1;
}

void bfs_visit(int u){
    for(int i=0; i<n; i++){
        nt[i] = 0;
        d[u] = 0;
    }

    color[u] = black;
    Q.push(u);
    while(!Q.empty()){
        int u = Q.front();
        int v = next(u);
        if(v != -1){
            if(color[v] == white){
                color[v] = black;
                d[v] = d[u] + 1;
                Q.push(v);
            }
        } else {
            Q.pop();
        }
    }
}

int main(){
    int u, k, v;
    scanf("%d", &n);
    for(int i=0; i<n; i++){
        color[i] = white;
    }
    for(int i=0; i<n; i++){
        cin >> u >> k;
        u--;
        for(int i=0; i<k; i++){
            cin >> v;
            v--;
            M[u][v] = 1;
        }
    }

    bfs_visit(0);

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

C++: //16D8103013E Sen Shunkou
#include<iostream>
#include<queue>
int n;
int cnt=0;

int main(){
    //input
    int n;
    std::cin>>n;

    int cnt=0;
    int A[100][100];
    int dis_min[n];
    bool visited[n];

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

    for(int i=0;i<n;i++){
        std::cin>>A[i][0];
        std::cin>>A[i][1];
        for(int j=0;j<A[i][1];j++){
            std::cin>>A[i][j+2];
        }
    }

    for(int i=0;i<n;i++){
        dis_min[i]=0;
    }

    //initialization
    std::queue<int> que;
    que.push(0);
    //std::cout<<"\n"<<que.front()<<"\n";
    //std::cout<<que.size()<<"\n\n";

    while(!que.empty()){
        int q=que.size();
        for(int k=0;k<q;k++){
            //std::cout<<"quesize"<<que.size()<<"\n";
            int i=que.front();
            que.pop();
            visited[i]=true;
            dis_min[i]=cnt;
            //std::cout<<i<<"cnt"<<cnt<<"\n";
            if(A[i][1]!=0){
                for(int j=0;j<A[i][1];j++){
                    if(visited[A[i][j+2]-1]!=true){
                        visited[A[i][j+2]-1]=true;
                        que.push(A[i][j+2]-1);
                        //std::cout<<A[i][j+2]-1<<"\n";
                    }
                }
            }
        }
        cnt++;
        //std::cout<<"cnt="<<cnt<<"\n";
    }

    //std::cout<<"===========\n";
    for(int i=0;i<n;i++){
        std::cout<<i+1<<" "<<dis_min[i]<<"\n";
    }
    return 0;
}