Go: package main

import (
	"bufio"
	"bytes"
	"fmt"
	"io"
	"os"
	"strconv"
	"strings"
)

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

type Graph struct {
	M [N][N]int
	d [N]int
}

func (g *Graph) bfs(s, n int) string {
	var q []int
	q = append(q, s) // push

	for i := 0; i < n; i++ {
		g.d[i] = INFTY
	}
	g.d[s] = 0

	for len(q) != 0 {
		u := q[0]
		q = q[1:] // pop
		for v := 0; v < n; v++ {
			if g.M[u][v] == 0 || g.d[v] != INFTY {
				continue
			}
			g.d[v] = g.d[u] + 1
			q = append(q, v) // push
		}
	}

	var out bytes.Buffer
	for i := 0; i < n; i++ {
		if g.d[i] == INFTY {
			out.WriteString(fmt.Sprintf("%d -1\n", i+1))
			continue
		}
		out.WriteString(fmt.Sprintf("%d %d\n", i+1, g.d[i]))
	}

	return strings.TrimRight(out.String(), "\n")
}

func answer(reader io.Reader) string {
	sc := bufio.NewScanner(reader)
	sc.Split(bufio.ScanWords)

	sc.Scan()
	n, _ := strconv.Atoi(sc.Text())

	var g Graph
	for i := 0; i < n; i++ {
		sc.Scan()
		u, _ := strconv.Atoi(sc.Text())
		sc.Scan()
		k, _ := strconv.Atoi(sc.Text())
		u--
		for j := 0; j < k; j++ {
			sc.Scan()
			v, _ := strconv.Atoi(sc.Text())
			v--
			g.M[u][v] = 1
		}
	}

	return g.bfs(0, n)
}

func main() {
	fmt.Println(answer(os.Stdin))
}

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

const int INF=99999999;

void get_dinetwork(int N,vector<vector<int>>& array){
    int u,k,x;

    for(int i=0;i<N;i++){
        cin>>u>>k;
        for(int j=0;j<k;j++){
            cin>>x;
            array[u-1][x-1]=1;
        }
    }

}

int bfs(int n,vector<vector<int>>& A,int v,vector<int>& d,vector<int>& flag){
        d[v]=0;
        flag[v]=1;
        queue<int> Q;
        for(int i=0;i<n;i++){if(A[v][i]==1){Q.push(i);}}
        int dmin;
        while(!Q.empty()){
                dmin=INF;
                for(int i=0;i<n;i++){if(A[i][Q.front()]==1 && d[i]<dmin){dmin=d[i];}}
                d[Q.front()]=dmin+1;
                flag[Q.front()]=1;
                for(int i=0;i<n;i++){if(A[Q.front()][i]==1 && flag[i]!=1){Q.push(i);}}
                Q.pop();
        }
}

int main(){
        cin.tie(0);
        ios::sync_with_stdio(false);

        int n;
        cin>>n;
        vector<vector<int>> array(n,vector<int>(n,0));
        get_dinetwork(n,array);

        //
        vector<int> d(n,INF);
        vector<int> flag(n,-1);
        //
        bfs(n,array,0,d,flag);
        //

        for(int i=0;i<n;i++){
                if(d[i]==INF){d[i]=-1;}
                cout<<i+1<<" "<<d[i]<<"\n";
        }

        return 0;

}

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

int N=100;
int INF = 1234567890;
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] = INF;
  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]!=INF) continue;
      d[v]=d[u]+1;
      q.push(v);
    }
  }
  for(int i=0;i<n;i++){
    if(d[i]==INF) cout<<i+1<<" "<<-1<<endl;
    else cout<<i+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);

}