Go: package main

import (
	"container/list"
	"fmt"
	"bufio"
	"os"
	"strconv"
)

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

var (
	n        int
	adj      [N][N]int
	distance [N]int
)

func BFS(start int) {
	q := list.New()
	q.PushBack(start)
	for i := 0; i < n; i++ {
		distance[i] = INF
	}
	distance[start] = 0
	u := 0
	for q.Len() != 0 {
		u = q.Remove(q.Front()).(int)
		for v := 0; v < n; v++ {
			if adj[u][v] == 0 {
				continue
			}
			if distance[v] != INF {
				continue
			}
			distance[v] = distance[u] + 1
			q.PushBack(v)
		}
	}
	for i := 0; i < n; i++ {
		var d int
		if distance[i] == INF {
			d = -1
		} else {
			d = distance[i]
		}
		fmt.Printf("%d %d\n", i+1, d)
	}
}

func main() {
	var u, k, v int
	scanner := bufio.NewScanner(os.Stdin)
	scanner.Split(bufio.ScanWords)
	scanner.Scan()
	n, _ = strconv.Atoi(scanner.Text())
	for i := 0; i < n; i++ {
		for j := 0; j < n; j++ {
			adj[i][j] = 0
		}
	}
	for i := 0; i < n; i++ {
		scanner.Scan()
		u, _ = strconv.Atoi(scanner.Text())
		u -= 1
		scanner.Scan()
		k, _ = strconv.Atoi(scanner.Text())
		for j := 0; j < k; j++ {
			scanner.Scan()
			v, _ = strconv.Atoi(scanner.Text())
			v -= 1
			adj[u][v] = 1
		}
	}
	BFS(0)
}

C++: #include <bits/stdc++.h>
using namespace std;

static int INFTY = (1<<21);
int n, M[100][100];
int d[100];

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++) {
        if (d[i] == INFTY) d[i] = -1;
        cout << i + 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 <bits/stdc++.h>
using namespace std;
typedef long long ll;
using Graph = vector<vector<int>>;

int main(void)
{
	// 頂点数と辺数
	int N;
	cin >> N;

	Graph G(N + 1);
	for (int i = 1; i <= N; i++)
	{
		int u, k, v;
		cin >> u >> k;
		for (int i = 0; i < k; i++)
		{
			cin >> v;
			G[u].push_back(v);
		}
	}

	// BFSのためのデータ構造
	vector<int> dist(N + 1, -1); // 全頂点を未訪問に初期化
	queue<int> que;

	// 初期条件
	dist[1] = 0;
	que.push(1); // 0を橙色頂点に

	// BFS開始
	while (!que.empty())
	{
		int v = que.front();
		que.pop();

		// vから辿れる頂点をすべて探索
		for (int nv : G[v])
		{
			if (dist[nv] != -1) continue; // 発見済みの頂点は探索しない

			//　新たな白色頂点 nv について距離情報を更新しキューに追加
			dist[nv] = dist[v] + 1;
			que.push(nv);
		}
	}

	// 結果出力 (各頂点の頂点 0 からの距離を見る)
	for (int v = 1; v <= N; ++v) cout << v << " " << dist[v] << endl;
}

C++: #include <iostream>
#include<string>
#include<cmath>
#include<algorithm>
#include<cctype>
#include<queue>
#include<stack>
#include<stdio.h>
#include<vector>
#include<set>
#include<map>
#include<array>
#include<iomanip>
#define rep(i,n) for(int i=0;i<n;i++)
using namespace std;
static const int N=100;
static const int inf=(1<<29);
int M[N][N];
int d[N];
int n;

void dfs(int u){
    rep(i,n)d[i]=inf;
    
    queue<int> q;
    q.push(u);
    d[u]=0;
    int l;
    while(!q.empty()){
        l=q.front();
        q.pop();
        for(int v=0;v<n;v++){
            if(M[l][v]==0)continue;
            if(d[v]!=inf)continue;
            d[v]=d[l]+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;
    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;
        }
    }
    dfs(0);
    
}

C++: #include <bits/stdc++.h>
#define _GLIBCXX_DEBUG
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define rrep(i, n) for (int i = 1; i < (n + 1); ++i)
using namespace std;
using ll = long long;
const int INF = +100100100;
// typedef pair<int,int> P;

vector<int> D(150, INF);
vector<vector<int>> M(150, vector<int>(150));
int n;

void bfs()
{
    int s = 0;
    queue<int> Q;
    Q.push(s);
    D[0]=0;
    while (!Q.empty())
    {
        int u = Q.front();
        Q.pop();
        rep(v, n)
        {
            // 訪れたことがない
            if (D[v] == INF&&M[u][v]==1)
            {
                D[v] = D[u] + 1;
                Q.push(v);
            }
        }
    }
    rep(i,n)if(D[i]==INF)D[i]=-1;
}

int main()
{
    cin >> n;
    vector<list<int>> L(n);
    rep(i, n)
    {
        int u, e;
        cin >> u >> e;
        rep(j, e)
        {
            int v;
            cin >> v;
            --v;
            L[i].push_back(v);
        }
    }
    
    rep(i, n)
    {
        rep(j, n)
        {
            list<int>::iterator it = find(L[i].begin(), L[i].end(), j);
            if (it != L[i].end())
            {
                M[i][j] = 1;
                L[i].erase(it);
            }
        }
    }
    bfs();
    rep(i,n){
        printf("%d %d\n",i+1,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];

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;
}