Go: package main

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
)

type vertexId int

type vertex struct {
	id vertexId
	visitedAt int
	adjs []vertexId
}

func createVertex(id int, adjsInt []int) vertex {
	adjs := make([]vertexId, len(adjsInt))
	for i := 0; i < len(adjs); i++ {
		adjs[i] = vertexId(adjsInt[i])
	}
	return vertex{
		id: vertexId(id),
		visitedAt: -1,
		adjs: adjs,
	}
}

func (v *vertex) isVisited() bool {
	return v.visitedAt >= 0
}

func bfs(id vertexId, vqueue []vertexId, vertices []vertex) {
	vertex := &vertices[id-1]
	for _, vid := range vertex.adjs {
		if !vertices[vid-1].isVisited() {
			(&vertices[vid-1]).visitedAt = vertex.visitedAt+1
			vqueue = append(vqueue, vid)
		}
	}
	if len(vqueue) > 0 {
		nextId := vqueue[0]
		nextVqueue := vqueue[1:]
		bfs(nextId, nextVqueue, vertices)
	}
}

func solveBfs(vertices []vertex) {
	vertex := &vertices[0]
	vertex.visitedAt = 0
	vqueue := make([]vertexId, 0)
	bfs(vertex.id, vqueue, vertices)
}

func main() {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)

	n, err := nextInt(sc)
	if err != nil {
		panic(err)
	}

	vertices := make([]vertex, n)
	for i := 0; i < n; i++ {
		id, err := nextInt(sc)
		if err != nil {
			panic(err)
		}
		adjN, err := nextInt(sc)
		if err != nil {
			panic(err)
		}
		adjs := make([]int, adjN)
		for j := 0; j < adjN; j++ {
			adjId, err := nextInt(sc)
			if err != nil {
				panic(err)
			}
			adjs[j] = adjId
		}
		vertices[i] = createVertex(id, adjs)
	}

	solveBfs(vertices)

	for i := 0; i < n; i++ {
		fmt.Printf("%d %d\n", vertices[i].id, vertices[i].visitedAt)
	}
}

func nextText(sc *bufio.Scanner) string {
	sc.Scan()
	return sc.Text()
}

func nextInt(sc *bufio.Scanner) (int, error) {
	return strconv.Atoi(nextText(sc))
}

C++: #include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <map>
#include <set>
#include <vector>
#include <stack>
#include <queue>
#include <bitset>
#include <algorithm>
#include <numeric>
#include <functional>
using namespace std;

#define Rep(b, e, i) for(int i = b; i <= e; i++)
#define Repr(e, b, i) for(int i = e; i >= b; i--)
#define rep(n, i) Rep(0, n-1, i)
#define repr(n, i) Repr(n-1, 0, i)
#define all(v) (v).begin(), (v).end()
#define pb(v) push_back(v)
#define uniq(v) (v).erase(unique(all(v)),(v).end())
#define bitcnt(x) __builtin_popcount(x)
#define fst first
#define snd second
#define Pqaz(T) priority_queue<T,vector<T>,greater<T>>
#define Pqza(T) priority_queue<T>
#define ENJYU std::ios::sync_with_stdio(false);std::cin.tie(0);

typedef long long ll;
typedef pair<ll, ll> llP;
typedef pair<int, int> intP;

//vector の中身を出力
template <class T>ostream &operator<<(ostream &o,const vector<T>&v)
{o<<"{";for(int i=0;i<(int)v.size();i++)o<<(i>0?", ":"")<<v[i];o<<"}";return o;}

const int MAX = 128;

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

void solve(void){
	ENJYU;
	int N;
	cin >> N;
	rep(N, i) {
		int u, k;
		cin >> u >> k;
		u--;
		rep(k, i) {
			int v;
			cin >> v;
			v--;
			adj[u].pb(v);
		}
	}
	memset(d, -1, sizeof(d));
	queue <int> q;
	q.push(0);
	d[0] = 0;
	while (!q.empty()) {
		int n = q.front();
		q.pop();
		for (int nv : adj[n]) {
			if (d[nv] > 0) continue;
			d[nv] = d[n] + 1;
			q.push(nv);
		}
	}

	rep(N, i) cout << i+1 << ' ' << d[i] << endl;

}

int main(void){
	solve();
	//cout << "yui(*-v・)yui" << endl;
	return 0;
}

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

#define rep(i,n) for (int i = 0; i < int(n); i++)
#define show(x) #x " = " << x

int n;
vector<int> G[100];
int d[100];

int main() {
    cin >> n;
    rep (i,n) {
        int u, k, v;
        cin >> u >> k;
        rep (i,k) cin >> v, G[u-1].push_back(v-1);
    }
    rep (i,100) d[i] = -1;

    queue<int> q;
    q.push(0);
    d[0] = 0;
    while (!q.empty()) {
        int v = q.front(); q.pop();
        rep (i,G[v].size()) {
            int x = G[v][i];
            if (d[x] == -1) {
                d[x] = d[v] + 1;
                q.push(x);
            }
        }
    }
    rep (i,n) cout << i+1 << " " << d[i] << endl;
        
}

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

struct Node{
	int s;
	queue<int> Q;
};

int main(){
	int n;
	cin >> n;
	Node node[n + 1];
	for(int i = 1; i <= n; i++){
		int u, k, v;
		cin >> u >> k;
		node[u].s = -1;
		while(k--){
			cin >> v;
			node[u].Q.push(v);
		}
	}

	int p = 1, next, m;
	queue<int> move;
	node[p].s = 0;
	move.push(p);

	while(!move.empty()){
		p = move.front();
		cout << "Pivot is " << p << endl;
		if(node[p].Q.empty()){
			cout << "Nowhere to go from " << p << endl;
			move.pop();
		} else {
			m = node[p].Q.size();
			while(m--){
				next = node[p].Q.front();
				node[p].Q.pop();
				cout << "Checking " << next << endl;
				if(node[next].s < 0){
					cout << "Can go to " << next << endl;
					node[next].s = node[p].s + 1;
					move.push(next);
				}
			}
			move.pop();
		}
	}

	for(int i = 1; i <= n; i++)
		cout << i << " " << node[i].s << endl;
}

C++: #include <iostream>
using namespace std;
#define INF 9999999

int dis[101]; //距離を格納
bool check[101];//訪問済みチェック
int main(){
  int n;
  cin>>n;
  fill(dis,dis+101,INF);
  dis[1]=0;
  check[1]=true;
  for(int i=0;i<n;i++){
    int u,k,v;
    cin>>u>>k;
    for(int j=1;j<=k;j++){
      cin>>v;
      if(check[v]){//訪問済みならば
        continue;
      }else{
        check[v]=true;
      }
      dis[v]=min(dis[u]+1,dis[v]);
    }
  }

  //表示部
  for(int i=1;i<=n;i++){
    cout<<i<<" ";
    if(dis[i]==INF)cout<<-1<<"\n";
    else  cout<<dis[i]<<"\n";
  }
}

C++: #include<iostream>
#include<algorithm>
#include<queue>
using namespace std;
static const int MAX=10000;
static const int INFTY = (1<<20);
static const int WHITE=0;
static const int GRAY=1;
static const int BLACK=2;

int n;
vector<pair<int,int> > adj[MAX];
void dijkstra(){
  priority_queue<pair<int,int> > PQ;
  int color[MAX];
  int d[MAX];
  for(int i=0;i<n;i++){
    d[i]=INFTY;
    color[i]=WHITE;
  }
  d[0]=0;
  PQ.push(make_pair(0,0));
  color[0]=GRAY;

  while(!PQ.empty()){
    pair<int,int>f=PQ.top();PQ.pop();
    int u=f.second;
    color[u]=BLACK;
    if(d[u]<f.first*(-1))continue;
    for(int j=0;j<adj[u].size();j++){
      int v=adj[u][j].first;
      if(color[v]=BLACK)continue;
      if(d[v]>d[u]+adj[u][j].second){
        d[v]=d[u]+adj[u][j].second;
        PQ.push(make_pair(d[v]*(-1),v));
        color[v]=GRAY;
      }
    }
  }
  for(int i=0;i<n;i++){
    cout<<i<<" "<<(d[i]==INFTY ? -1:d[i])<<endl;
  }
}

int main(){
  int k,u,v,c;
  cin>>n;
  for(int i=0;i<n;i++){
    cin>>u>>k;
    for(int j=0;j<k;j++){
      cin>>v>>c;
      adj[u].push_back(make_pair(v,c));
    }
  }
  dijkstra();
  return 0;
}

C++: #include<iostream>
#include<queue>
#define N 101
using namespace std;
int A[N][N];
bool visited[N];
int n;
int d[N];
int distance;
queue<int> node;

void bfs(){
    while(!node.empty()){
        int temp=node.front();
        for(int i=0;i<n;i++){
            if(temp==i) continue;
            if(!visited[i] && A[temp][i]==1){
                d[i]=d[temp]+1;
                visited[i]=true;
                node.push(i);
            }
        }
        node.pop();
    }
}

int main(){
    int k,num;
    int e;
    cin>>n;
    for(int i=0;i<n;i++){
        visited[i]=false;
        d[i]=-1;
        for(int j=0;j<n;j++)
            A[i][j]=0;
    }
    for(int i=0;i<n;i++){
        cin>>k;
        k--;
        cin>>num;
        for(int j=0;j<num;j++){
            cin>>e;
            e--;
            A[k][e]=1; //A[e][k]=1;
        }
    }

    node.push(0);
    visited[0]=true;
    d[0]=0;
    bfs();

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

    return 0;

}