Go: package main

import "fmt"

type container struct {
	data []int
}

func (c *container) queue(v int) {
	c.data = append(c.data, v)
}
func (c *container) dequeue(p *int) bool {
	if p == nil || len(c.data) == 0 {
		return false
	}
	*p = c.data[0]
	c.data = c.data[1:len(c.data)]
	return true
}

func main() {
	var n int
	fmt.Scan(&n)
	g := make([][]int, n+1) // 1-indexed
	d := make([]int, n+1)   // 1-indexed
	for i := 1; i <= n; i++ {
		d[i] = -1
		var u, k, v int
		fmt.Scan(&u, &k)
		for j := 0; j < k; j++ {
			fmt.Scan(&v)
			g[u] = append(g[u], v)
		}
	}

	var q container
	d[1] = 0
	q.queue(1)

for len(q.data) > 0  { // 幅優先探索
		var v int
		q.dequeue(&v)
		for i := 0; i < len(g[v]); i++ {
			nv := g[v][i]
		if d[nv] == -1 { // 未訪問
				q.queue(nv)
				d[nv] = d[v] + 1
			}
		}
	}
	for i := 1; i <= n; i++ {
		fmt.Printf("%d %d\n", i, d[i])
	}
}

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<100;i++){
        for(int j=0;j<100;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]=-1;
    }

    //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";

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

    return 0;
}

C++: #include <iostream>
#include <vector>
#include <cmath>
#include <string>
#include <algorithm>
#include <iomanip>
#include <map>
#include <bitset>
#include <cstdio>
#include <set>
#include <stack>
#include <queue>
#include <cassert>
#include <numeric>
using namespace std;
typedef long long ll;
#define FOR(i,a,b) for (ll i=(a),__last_##i=(b);i<__last_##i;i++)
#define RFOR(i,a,b) for (ll i=(b)-1,__last_##i=(a);i>=__last_##i;i--)
#define REP(i,n) FOR(i,0,n)
#define RREP(i,n) RFOR(i,0,n)
#define __GET_MACRO3(_1, _2, _3, NAME, ...) NAME
#define rep(...) __GET_MACRO3(__VA_ARGS__, FOR, REP)(__VA_ARGS__)
#define rrep(...) __GET_MACRO3(__VA_ARGS__, RFOR, RREP)(__VA_ARGS__)
template<typename T> istream &operator>>(istream &is, vector<T> &v){ for (auto &x : v) is >> x; return is; }
template<typename T> ostream& operator<<(ostream& os, const vector<T>& v) {
    REP(i,v.size()){if(i)os<<" ";os<<v[i];}return os;}
template<typename T> ostream& operator<<(ostream& os, const vector<vector<T>>& v) {
    REP(i,v.size()){if(i)os<<endl;os<<v[i];}return os;}
#define vi vector<int>
#define vii vector<vector<int>>
#define mii map<int,int>
#define Sort(v) sort(v.begin(),v.end())
#define Reverse(v) reverse(v.begin(),v.end())
#define ALL(a)  (a).begin(),(a).end()
#define pb push_back
#define mp make_pair
//#define int ll

const int md = 1000000007;
const int INF = 1<<30;



int main(){
    int n; cin >> n;
    vector<vector<int>> e(n);


    rep(i,n){
        int s; cin >> s;
        int tmp; cin >> tmp;
        rep(j,tmp){
            int to; cin >> to;
            e[i].push_back(to-1);
        }
    }

    vi ans(n);
    rep(i,n){
        //if(i != 3) continue;
        queue<pair<int,int>> bfs;
        bfs.emplace(0,0);
        while(!bfs.empty()){
            auto tmp = bfs.front();
            if(tmp.first == i) {
                ans[i] = tmp.second;
                break;
            }
            bfs.pop();

            rep(j,e[tmp.first].size()){
                bfs.emplace(e[tmp.first][j],tmp.second+1);
            }
        }
    }

    rep(i,n){
        cout << i+1 << " " << ans[i] << endl;
    }
}

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

using vvi = std::vector<std::vector<int>>;

std::vector<int> DistanseFrom(const vvi& edges, int from)
{
    using namespace std;
    constexpr int nil = -1;

    int nextDist {};
    const int n = edges.size();
    queue<int> currentQ;
    queue<int> nextQ;
    vector<int> distances(n, nil);

    nextQ.push(from);
    distances[from] = nextDist;
    ++nextDist;

    while (!nextQ.empty())
    {
        currentQ = nextQ;
        nextQ = {};
        
        while (!currentQ.empty())
        {
            int c = currentQ.back();
            currentQ.pop();

            for (const auto& e : edges[c])
            {
                if (distances[e] == nil)
                {
                    nextQ.push(e);
                    distances[e] = nextDist;
                }
            }
        }
        
        ++nextDist;
    }

    return distances;
}

void solve()
{
    using namespace std;

    int n;
    cin >> n;

    //隣接リスト形式(1オリジン)
    vvi edges(n + 1);

    //読み込み
    for (int i = 1; i <= n; ++i)
    {
        int u, k;
        cin >> u >> k;

        edges[u] = vector<int>(k);

        for (int j = 0; j < k; ++j)
        {
            cin >> edges[u][j];
        }
    }

    auto dist = DistanseFrom(edges, 1);

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

int main()
{
    solve();
    return 0;
}

C++: #include <iostream>
#include <vector>
#include <queue>
using namespace std;
#define INF 1e9
#define EXIST 1
int graph[200][200];
int dist[200];
int n;

void bfs() {
  queue<int> next;
  next.push(0);
  dist[0] = 0;
  
  while (!next.empty()) {
    int current = next.front();
    next.pop();
    for (int i = 0; i < n; i++) {
      if (graph[current][i] == EXIST && dist[i] > dist[current]+1) {
        next.push(i);
        dist[i] = dist[current]+1;
      }
    }
  }  
}

int main() {
  cin >> n;
  for (int i = 0; i < n; i++) {
    dist[i] = INF;
    int u, k, v; cin >> u >> k;
    for (int j = 0; j < k; j++) {
      cin >> v;
      graph[u-1][v-1] = EXIST;
    }
  }
  
  bfs();
  
  for (int i = 0; i < n; i++) {
    cout << i+1 << " ";
    cout << (dist[i] == INF ? -1 : dist[i]) << endl;
  }
}

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

#define MAX 100
#define NIL -2

int n, G_list[MAX+1];
int G[MAX+1][MAX+1];
int d[MAX+1][2];

void init(void){
  for(int i=0; i<=MAX; i++){
    d[i][0]=-1;
  }
}

void make_graph(void){
  scanf("%d", &n);

  for(int i=0; i<n; i++){
    int cnt, num, m;

    scanf("%d %d", &num, &cnt);
    G_list[i]=num;

    for(int j=0; j<cnt; j++){
      scanf("%d", &m);
      G[num][m]=1;
    }
  }
}

void check_depth(void){
  queue<int> Q;
  Q.push(G_list[0]);
  d[G_list[0]][0]=0;
  d[G_list[0]][1]=NIL;
  
  while(!Q.empty()){
    int top=Q.front();
    Q.pop();
    
    for(int j=0; j<n; j++){
      if(G[top][G_list[j]] == 1 && d[G_list[j]][1] != NIL){
	d[G_list[j]][0]=d[top][0]+1;
	d[G_list[j]][1]=NIL;
	Q.push(G_list[j]);
      }
    }
  }
}

void print(void){

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

int main(void){

  init();
  make_graph();
  check_depth();
  print();
  
  return 0;
}