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<stdio.h>
#include<stack>
#include<iostream>
#include<string>
using namespace std;

int n = 0;//pointing at number of line
int u = 0;//number of top
int k[101];//output order(connect)
int v[101][101];//number of top
int Short[101] = { 0 };//Short(d[v])
//into n = 0;//element count
int p = 0;//Pointer
int fptr = 0;
int lptr = 0;
int x1[10000];
int y1[10000];
void Enqueue(int y, int x)
{
	x1[lptr] = x;//top of number
	y1[lptr] = y;//shortest
	lptr = (lptr + 1) % 10000;
}
void bfs(int l) {
	int i;
	while (fptr!=lptr) {
		l=x1[fptr];
		p=y1[fptr];
		fptr = (fptr + 1) % 10000;
		if(Short[l]!=-1){
			continue;
		}
		for(i=0;i<k[l];i++){
			if(v[l][i]){
				Enqueue(p+1,v[l][i]);
			}
		}
		//Enqueue(v[l][in]);
		Short[l]=++p;
	}
}
int main()
{
	int i;
	int j;
	cin >> n;
	for (i = 0; i < n; i++) {
		cin >> u;
		cin >> k[u];
		for (j = 0; j < k[u]; j++) {
			cin >> v[u][j];
		}
	}
	Enqueue(-1,1);
	for(i=0;i<n+1;i++){
		Short[i]=-1;
	}
	bfs(0);
	
	for (i = 1; i < n + 1; i++) {
		cout << i << " " << Short[i] << endl;
	}
}

C++: #include <iostream>
#include <queue>
#include <vector>
using namespace std;
int d[128][128],solve[128];
int main(){
      //input
      int n,m,row,t;
      queue<int> que;
      cin >> n;
      for(int i= 0;i<n;i++){
            cin >>row>>m;
            for(int j = 0;j<m;j++){
                  cin>>t;
                  d[row][t] = 1;
            }
      }
      //debug
      //for(int i = 0;i<=n;i++){
      //for(int j = 0;j<=n;j++)cout << d[i][j] << ' ';cout << endl;}

      //solve
      fill(solve,solve+n+2,-1);
      que.push(1);
      solve[1] = 0;
      while(!que.empty())
      {
            int p = que.front();
            que.pop();
            for(int i = 1;i<=n;i++)
            {
                  if(d[p][i] && solve[i]==-1)
                  {
                        que.push(i);
                        solve[i] = solve[p] + 1;
                  }
            }
      }
      for(int i = 1;i<=n;i++)
            cout << i << ' '<< solve[i]<<endl;


}

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 < 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>
#include <vector>
using namespace std;
int d[128][128],solve[128];
int main(){
      int n,m,row,t;
      queue<int> que;
      cin >> n;
      for(int i= 0;i<n;i++){
            cin >>row>>m;
            for(int j = 0;j<m;j++){
                  cin>>t;
                  d[row][t] = 1;
            }
      }
      fill(solve,solve+n+2,-1);
      que.push(1);
      solve[1] = 0;
      while(!que.empty()){
            int p = que.front();
            que.pop();
            for(int i = 1;i<=n;i++){
                  if(d[p][i] && solve[i]==-1){
                        que.push(i);
                        solve[i] = solve[p] + 1;
                  }
            }
      }
      for(int i = 1;i<=n;i++)cout << i << ' '<< solve[i]<<endl;
}

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

int n, u, k, v;
int a[100][100] = {{0}};
int b[100] = { - 1 };
queue<int> q;

int main() {
	cin >> n;
	for ( int i = 0; i < n; i++ ) {
		cin >> u >> k;
		for ( j = 0; j < k; j++ ) {
			cin >> v;
			a[u - 1][v - 1] = 1;
		}
	}
	b[0] = 0;
	q.push( 0 );
	while ( ! q.empty() ) {
		u = q.front();
		for ( int i = 0; i < n; i++ ) {
			if ( a[u][i] == 1 && b[i] == -1 ) {
				b[i] = b[u] + 1;
				q.push( i );
			}
		}
		q.pop();
	}
	for ( int i = 0; i < n; i++ )
		cout << ( i + 1 ) << " " << b[i] << endl;
}

C++: #include<iostream>
#include<queue>
using namespace std;
int n, d[100], M[100][100];
queue<int>q;
void bfs(int u){
	q.push(u);
	while(!q.empty()){
		int v=q.front();
		q.pop();
		for(int i=0; i<n; i++){
			if(M[v][i]==1 && d[i]==-1){
				d[i]=d[v]+1;
				q.push(i);
			}
		}
	}
}
int main(){
	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++)
		d[i]=-1;
	d[0]=0;
	for(int i=0; i<n; i++){
		int id,k;
		cin>>id>>k;
		for(int j=0; j<k; j++){
			int child;
			cin>>child;
			M[id-1][child-1]=1;
		}
	}
	bfs(0);
	for(int i=0; i<n; i++)
		cout<<i+1<<" "<<d[i]<<endl;
	return 0;
}

C++: #include <stdio.h>
#include <iostream>
#include <utility>
#include <algorithm>
#include <math.h>
#include <vector>
#include <list>
#define inf 200
using namespace std;

int n;
list<int> adj[101];
int d[101];
bool f[101];
void BFS(int v)
{
    int m = 0;
    f[v] = false;
    while (!adj[v].empty())
    {
        d[adj[v].front()] = min(d[v] + 1, d[adj[v].front()]);
        adj[v].pop_front();
    }
    for (int i = 1; i <= n; i++)
    {
        if (f[i] && d[i] < d[m])
            m = i;
    }
    if (m > 0)
        BFS(m);
}

void print()
{
    for (int i = 1; i <= n; i++)
    {
        if (d[i] == inf)
            d[i] = -1;
        printf("%d %d\n", i, d[i]);
    }
}

int main()
{
    int u, k, v;
    cin >> n;

    for (int i = 0; i < n; i++)
    {
        cin >> u >> k;
        while (k > 0)
        {
            cin >> v;
            adj[u].push_back(v);
            k--;
        }
    }
    for (int i = 0; i <= n; i++)
    {
        d[i] = inf;
        f[i] = true;
    }
    d[1] = 0;
    BFS(1);

    print();

    return 0;
}