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

int A[101][101] = {0};
int n, tt = 0, d[101] = {0}, color[101] = {0};
queue<int> Q;


void bfs (int u) {
    int i, j ,k;
    Q.push(u);
    d[u] = tt++;
    color[u] = 1;
    while ( !Q.empty() ) {
        j = Q.front();
        Q.pop();
        for ( i = 1; i <= n; i++ ) {
            if ( A[j][i] == 1 && color[i] != 1 ) {
                Q.push(i);
                color[i] = 1;
                d[i] = d[j] + 1;
            }

        }
        }
    }



int main() {
    int i, j, k, v;
    cin >> n;
    for ( i = 0; i < n; i++ ) {
        cin >> j >> k;
        while ( k-- ) {
            cin >> v;
            A[j][v] = 1;
        }
    }

    bfs(1);
    for ( i = 1; i <= n; i++ ) if ( color[i] != 1 ) d[i] = -1;
    for ( i = 1; i <= n; i++ ) cout << i << ' ' << d[i] << endl;

    return 0;

}

C++: #include<iostream>
#include<queue>
using namespace std;
int N;
int D[101];
void bfs(int src){
    int u[101],k[101],a[10010],d[101][101];
    bool visit[101];
    for(int i=1;i<=N;++i){
        cin>>u[i]>>k[i];
        for(int j=0;j<k[i];++j){
            cin>>a[j];
            d[u[i]][a[j]]=1;
        }
        visit[i]=true;
    }
    queue<int>Q;
    Q.push(src);
    D[src]=0;
    visit[src]=false;
    while(!Q.empty()){
        int cur=Q.front();
        Q.pop();
        for(int i=1;i<=N;++i){
            if(d[cur][i]==1&&visit[i]){
                visit[cur]=false;
                visit[i]=false;
                D[i]=D[cur]+1;
                Q.push(i);
            }
        }
    }
    for(int i=1;i<=N;++i){
        if(i!=1&&D[i]==0){
            D[i]=-1;
        }
        cout<<i<<" "<<D[i]<<endl;
    }
}
int main(){
    cin>>N;
    int start=1;
    bfs(start);
}

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

int M[101][101], cond[101], d[101], n;

void setAdj()
{
	int u, k, v;
	for (int i = 0; i < n; i++) {
		cin >> u >> k;
		for (int j = 0; j < k; j++) {
			cin >> v;
			M[u][v] = 1;
		}
	}
}

void bfs(int x)
{
	queue<int> Q;

	Q.push(x);
	cond[x] = -1;
	d[x] = 0;

	while (!Q.empty()) {
		int u = Q.front();
		for (int i = 1; i <= n; i++) {
			if (M[u][i] == 1 && cond[i] == 0) {
				Q.push(i);
				d[i] = d[u] + 1;				
				cond[i] = -1;
			}
		}
		Q.pop();
		cond[u] = 1;
	}
}

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

	cin >> n;
	setAdj();

	for (int i = 1; i <= n; i++)
		if (cond[i] == 0) bfs(i);

	for (int i = 1; i <= n; i++)
		cout << i << " " << d[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,Mtw[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 utw;
    while(!q.empty()){
        utw=q.front(); q.pop();
        for(int v=0;v<n;v++){
            if(Mtw[utw][v]==0)continue;
            if(d[v]!=INFTY)continue;
            d[v]=d[utw]+1;
            q.push(v);
        }
    }
    for(int i=0;i<n;i++){
        cout<<i+1<<" "<<((d[i]==INFTY)?(-1):d[i])<<endl;
    }
}

int main(){
    int utw,ktw,vtw;

    cin >> n;
    for(int i=0;i<n;i++){
        for(int j=0;j<n;j++)Mtw[i][j]=0;
    }

    for(int i=0;i<n;i++){
        cin>>utw>>ktw;
        utw--;
        for(int j=0;j<ktw;j++){
            cin >> vtw;
            vtw--;
            Mtw[utw][vtw]=1;
        }
    }

    bfs(0);

    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[u] != 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;
}

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;
  int i,j;

  cin >> n;
  for(i=0;i < n;i++)
    {
      for(j=0;j < n;j++)
        {
          M[i][j] = 0;
        }
    }

  for(i=0;i < n;i++)
    {
      cin >> u >> k;
      u--;
      for(j=0;j < k;j++)
        {
          cin >> v;
          v--;
          M[u][v] = 1;
        }
    }

  bfs(0);

  return 0;

}