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) {
			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 <queue>
using namespace std;
static const int MAX = 100;
static const int WHITE = 0;
static const int GRAY = 1;
static const int BLACK = 2;
static const int NIL = -1;
int M[MAX][MAX], n;
int d[MAX], color[MAX];
queue<int> Q;

void bfs(int s)
{
    int u, v;
    Q.push(s);
    color[s] = GRAY;
    d[s] = 0;
    while (!Q.empty())
    {
        u = Q.front();
        Q.pop();
        for (int v = 0; v != n; ++v)
        {
            if (M[u][v] && color[v] == WHITE)
            {
                Q.push(v);
                color[v] = GRAY;
                d[v] = d[u] + 1;
            }
        }
        color[u] = BLACK;
    }
}

int main()
{
    int id, m, v;
    cin >> n;
    for (int i = 0; i != MAX; ++i)
    {
        d[i] = NIL;
        color[i] = WHITE;
        for (int j = 0; j != MAX; ++j)
        {
            M[i][j] = 0;
        }
    }
    for (int i = 0; i != n; ++i)
    {
        cin >> id >> m;
        for (int j = 0; j != m; ++j)
        {
            cin >> v;
            M[id-1][v-1] = 1;
        }
    }
    bfs(0);

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

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

using namespace std;

#define N 100
#define INFTY 99999999

int n,
// 隣接行列
M[N][N];
// 距離 colorも同時に管理する
int d[N];

void bfs(int s){
    queue<int> q;
    q.push(s);
    
    // 距離を初期化
    for(int i = 0;i < n;++i){
        d[i] = INFTY;
    }
    d[s] = 0;
    // 対象の頂点番号
    int u;
    
    while(!q.empty()){
        u = q.front();
        q.pop();
        
        for(int v = 0;v < n;++v){
            // 頂点が隣接しているかつ未訪問
            if(M[u][v] == 1 && d[v] == INFTY){
                // 対象の頂点の距離は前の頂点 + 1
                d[v] = d[u] + 1;
                q.push(v);
            }
        }
    }
    
}

int main(){
    int u,k,v;
    
    cin >> n;
    
    // 隣接行列を初期化
    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;
        // 頂点を移動する
        u--;
        // 頂点の数だけ回す
        for(int j = 0;j < k;++j){
            cin >> v;
            --v;    // ずらす
            M[u][v] = 1;
        }
    }
    
    bfs(0);

    for(int i = 0;i < n;++i){
        cout << i + 1 << " " << ((d[i] == INFTY) ? (-1) : 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);
	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[u] != 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 <queue>
using namespace std;

void bfs(int);

static const int Q = 100;
static const int W = (1<<21);

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

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;
}
    

void bfs(int s){
  queue<int> q;
  q.push(s);

  for(int i=0;i<n;i++){
    d[i]=W;
  }
  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]!=W)continue;
      d[v]=d[u]+1;
      q.push(v);
    }
  }

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

C++: #include<bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair<int, int> P;

#define vi vector<int>
#define vl vector<long long>
#define vvi vector< vector<int> >
#define vvl vector< vector<ll> >
#define REP(i, n) for (int i = 0; i < (int)(n); i++)
#define REPD(i, n) for (int i = (int)(n-1); i >= 0; i--)
#define FOR(i, a, b) for (int i = (int)(a); i < (int)(b); i++)
#define FORD(i, a, b) for (int i = (int)(a); i >= (int)(b); i--)
#define INF 1e18
#define MOD 1e9+7

template<class T> bool chmax(T &a, const T & b) {
    if (a<b) {
        a = b;
        return true;
    }
    return false;
}

template<class T> bool chmin(T &a, const T & b) {
    if (a>b) {
        a = b;
        return true;
    }
    return false;
}

const int MAX_N = 110;
vector < vector<int> > G;
int d[MAX_N];

void bfs(int s) {
    d[s] = 0;
    queue<int> q;
    q.push(s);
    while (!q.empty()) {
        int u = q.front(); q.pop();
        REP(i, (int)G[u].size()) {
            int v = G[u][i];
            if (d[v] != -1) continue;
            d[v] = d[u]+1;
            q.push(v);
        }
    }
}

int main() {
    int n;
    cin >> n;
    G.resize(n);
    REP(i, n) {
        d[i] = -1;
        int u, k;
        cin >> u >> k;
        --u;
        REP(j, k) {
            int v;
            cin >> v;
            --v;
            G[u].push_back(v);
        }
    }

    bfs(0);
    REP(i, n) {
        cout << i+1 << ' ' << d[i] << endl;
    }
}