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 <vector>
#include <queue>

using namespace std;

struct Node {
    bool visit = false;
    vector<int> next;
    int d = -1;
};

int main() {
    int n, id, k, temp;
    Node node[101];
    queue<int> que;
    
    cin >> n;
    for (int i = 0; i < n; i++) {
        cin >> id >> k;
        for (int j = 0; j < k; j++) {
            cin >> temp;
            node[id].next.push_back(temp);
        }
    }

    node[1].d = 0;
    node[1].visit = true;
    que.push(1);
    while (!que.empty()) {
        temp = que.front();
        for (int i = 0; i < node[temp].next.size(); i++) {
            if (node[node[temp].next[i]].visit == false) {
                node[node[temp].next[i]].d = node[temp].d + 1;
                node[node[temp].next[i]].visit = true;
                que.push(node[temp].next[i]);
            }
        }
        que.pop();
    }

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

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

const int INF = 0x3f3f3f3f;
int t1, t2, t3, n, e[105][105];

int main() {
	cin >> n;
	for (int i = 1; i <= n; i++) {
		for (int j = 1; j <= n; j++) e[i][j] = INF;
		e[i][i] = 0;
	}
	for (int i = 0; i < n; i++) {
		cin >> t1 >> t2;
		for (int j = 0; j < t2; j++) {
			cin >> t3;
			e[t1][t3] = 1;
		}
	}
	for (int i = 1; i <= n; i++) {
		for (int j = 1; j <= n; j++) {
			for (int k = 1; k <= n; k++) {
				e[j][k] = min(e[j][k], e[j][i] + e[i][k]);
			}
		}
	}
	for (int i = 1; i <= n; i++) {
		cout << i << ' ' << ((e[1][i] == INF) ? -1 : e[1][i]) << endl;
	}
}

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

static const int N = 100;
static const int INFTY = (1 << 21);

int d[N] = {0};

void bfs(int M[N][N], int n, 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 n;
    cin >> n;

    int M[N][N] = {0};
    int u, k, v;
    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(M, n, 0);

    return 0;
}

C++: #include <iostream>
#include <vector>
#include <algorithm>
#include <cmath>
#include <string>
#include <queue>
#include <stack>
#include <set>
#include <map>
#include <iomanip>
#include <utility>
#include <tuple>
#include <functional>
#include <bitset>
#include <cassert>
#include <complex>
#include <stdio.h>
#include <time.h>
#include <numeric>
#include <unordered_map>
#include <unordered_set>
# define ll int64_t
# define str string
# define rep(i,n) for(ll i=0;i<n;i++)
# define rrep(i,n) for(ll i=1;i<=n;i++)
# define ALL(x) (x).begin(), (x).end()
# define SZ(x) ((int)(x).size())
# define pb push_back
# define mod 1000000007
# define PI 3.141592653589793
# define vec vector
#define dump(x) cerr<<#x<<"="<<x<<endl
using namespace std;

#define INF 2000000000
#define MAX_V 10



bool compare_by_b(pair<string,ll> a,pair<string,ll> b){
    if(a.second != b.second) return a.second<b.second;
    else return a.first<b.first;
}

bool my_compare(pair<string,ll> a,pair<string,ll> b){
    if(a.first != b.first) return a.first<b.first;
    if(a.second != b.second) return a.second>b.second;
    else return true;
}

ll modpow(ll a,ll n,ll mod1) {
    ll res=1;
    while(n>0){
        if(n&1) res=res*a%mod1;
        a = a*a%mod1;
        n >>= 1;
    }
    return res;
}

ll factorial(ll n){
    ll x=1;
    rrep(i,n) (x*=i)%=mod;
    return x;
}

ll gcd(ll a,ll b){
   if (a%b == 0) return(b);
   else return(gcd(b,a%b));
}

ll lcm(ll a,ll b){
   return a/gcd(a,b)*b;
}

using graph = vector<vector<ll>>;

int main(){
    cin.tie(0);
    ios::sync_with_stdio(false);
    
    ll n;
    cin>>n;
    graph g(n+1);
    rep(i,n){
        ll u,k;
        cin>>u>>k;
        rep(j,k){
            ll a;
            cin>>a;
            g[u].pb(a);
        }
    }
    
    vec<ll> dist(n+1,-1);
    queue<ll> que;
    dist[1]=0;
    que.push(1);
    
    while(!que.empty()){
        ll v=que.front();
        que.pop();
        for(auto nv : g[v]){
            if(dist[nv]==-1){
                dist[nv]=dist[v]+1;
                que.push(nv);
            }
        }
    }
    rrep(i,n){
        cout<<i<<" "<<dist[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[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<k;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;
}