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<bits/stdc++.h>
#define rep(i, n) for (int i = 0; i < (int) (n); i++)
using namespace std;

#define MAX 100

int d[MAX], t = 0, M[MAX][MAX] = {}, n;

void bfs(){
    queue<int> todo;
    d[0] = 0;
    todo.push(0);
    while(!todo.empty()){
        int m = todo.front();
        todo.pop();
        rep(i, n){
            if(d[i] == -1 && M[m][i]){
                d[i] = d[m] + 1;
                todo.push(i);
            }
        }
    }
    return;
}

int main(){
    cin >> n;
    fill(d, d + n, -1);
    int m, l;
    rep(i, n){
        cin >> m >> l;
        rep(j, l){
            int o;
            cin >> o;
            M[m - 1][o - 1] = 1;
        }
    }
    bfs();
    rep(i, n){
        cout << i + 1 << " " << d[i] << endl;
    }
    
    return 0;
}

C++: #include <iostream>
#include <cstdio>
#include <string>
#include <algorithm>
#include <utility>
#include <cmath>
#include <vector>
#include <stack>
#include <queue>
#define rep(i, n) for(int i = 0; i < n; i++)
using namespace std;
typedef long long ll;
ll mod = 1000000007;

const int N = 100;
const int INF = (1 << 21);

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

void bfs(int s) {
    queue<int> Q;
    Q.push(s);
    rep(i, n) {
        d[i] = INF;
    }
    d[s] = 0;
    int u;
    while( !Q.empty() ) {
        u = Q.front();
        Q.pop();
        rep(v, n) {
            if(M[u][v] == 0) {
                continue;
            }
            if(d[v] != INF) {
                continue;
            }
            d[v] = d[u] + 1;
            Q.push(v);
        }
    }

    rep(i, n) {
        cout << i+1 << " " << ( (d[i] == INF) ? (-1) : d[i] ) << endl;
    }
}

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

    cin >> n;
    rep(i, n) {
        rep(j, n) {
            M[i][j] = 0;
        }
    }

    rep(i, n) {
        cin >> u >> k;
        u--;
        rep(j, k) {
            cin >> v;
            v--;
            M[u][v] = 1;
        }
    }

    bfs(0);
    
    return 0;
}

C++: #include <iostream>
#include<stdio.h>
#include<stack>
#include<queue>

#define MAX 100
#define WHITE 1
#define GRAY 2
#define BLACK 3

using namespace std;

int color[MAX], d[MAX], f[MAX];
int n, A[MAX][MAX];
int nt[MAX];
int dis[MAX]; //?????¶???????????????????????????
int tt = 0;

void dfs_visit_1(int u) { //???????????°
    color[u] = GRAY;
    d[u] = ++tt;
    for(int v = 0; v < n; v++) {
        if(A[u][v] == 0) continue;
        if(color[v] == WHITE) dfs_visit_1(v);
    }
    color[u] = BLACK;
    f[u] = ++tt;
}

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

void dfs_visit_2(int u) { //????????°
    for(int i = 0; i < n; i++) nt[i] = 0;
    color[u] = GRAY;
    d[u] = ++tt;
    stack<int> S;
    S.push(u);

    while(!S.empty()) {
        int u = S.top();
        int v = next(u);
        if(v != -1) {
            if(color[v] == WHITE) {
                color[v] = GRAY;
                d[v] = ++tt;
                S.push(v);
            }
        }else {
            S.pop();
            color[u] = BLACK;
            f[u] = ++tt;
        }
    }
}

void dfs() { // ?????????????????°
    for(int i = 0; i < n; i++) {
        color[i] = WHITE;
        nt[i] = 0;
    }
    tt = 0;
    for(int i = 0; i < n; i++) {
        if(color[i] == WHITE) dfs_visit_2(i);
    }
    for(int i = 0; i < n; i++) {
        printf("%d %d %d\n", i+1, d[i], f[i]);
    }
}

void bfs(int u) {
    dis[0] = 0;
    for(int i = 1; i < n; i++) dis[i] = -1;
    queue<int> Q;
    Q.push(u);
    while(!Q.empty()) {
      int u = Q.front();
      Q.pop();
        for(int v = 0; v < n; v++) {
            if(A[u][v] == 1 && dis[v] == -1) {
                Q.push(v);
                dis[v] = dis[u] + 1;
            }
        }
    }

    for(int i = 0; i < n; i++) {
        printf("%d %d\n", i+1, dis[i]);
    }
}

int main()
{
    int u, k, v;
    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);
            A[u-1][v-1] = 1;
        }
    }

    /*
    for(int i = 0; i < n; i++) {
        for(int j = 0; j < n; j++) {
            printf("%d", A[i][j]);
            if(j != n-1) printf(" ");
        }
        printf("\n");
    }
    */
    //dfs();
    bfs(0);

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

  bfs(0);

  return 0;
}