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 <map>
#include <set>
#include <list>
#include <cmath>
#include <queue>
#include <stack>
#include <cstdio>
#include <string>
#include <vector>
#include <complex>
#include <cstdlib>
#include <cstring>
#include <numeric>
#include <sstream>
#include <iostream>
#include <algorithm>
#include <functional>
 
#define mp       make_pair
#define pb       push_back
#define all(x)   (x).begin(),(x).end()
#define rep(i,n) for(int i=0;i<(n);i++)
 
using namespace std;
 
typedef    long long          ll;
typedef    unsigned long long ull;
typedef    vector<bool>       vb;
typedef    vector<int>        vi;
typedef    vector<vb>         vvb;
typedef    vector<vi>         vvi;
typedef    pair<int,int>      pii;
 
const int INF=1<<29;
const double EPS=1e-9;
 
const int dx[]={1,0,-1,0},dy[]={0,-1,0,1};

std::vector<vector<int> > G;
std::vector<int> flag;
std::vector<int> in;
int N;
typedef pii P;

int main(int argc, char const *argv[]) {
	
	cin >> N;

	for (int i = 0; i < N; ++i) {
		G.push_back(vector<int>());
		flag.push_back(0);
		in.push_back(100000000);
		for (int j = 0; j < N; ++j) {
			G[i].push_back(0);
		}
	}

	for (int i = 0; i < N; ++i) {
		int u, k;
		cin >> u >> k;
		u--;
		for (int j = 0; j < k; ++j) {
			int v;
			cin >> v;
			v--;
			G[u][v] = 1;
		}
	}
	queue<P> q;
	q.push(mp(0, 0));
	while(!q.empty()) {
		P u = q.front(); q.pop();
		int dist = u.second;
		if (dist > in[u.first]) continue;
		in[u.first] = dist;
		flag[u.first] = 1;
		for (int i = 0; i < N; ++i) {
			if (flag[i] == 0 && G[u.first][i] == 1) {
				q.push(mp(i, dist + 1));
			}
		}
	}

	for (int i = 0; i < N; ++i) {
		if (in[i] == 100000000) {
			in[i] = -1;
		}
		cout << i + 1 << " " << in[i] << endl;
	}

	return 0;
}

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

/*

void bfs(int vertex, int depth)
{
  seen[vertex] = true;
  ans [vertex] = depth;
  for (auto &&i : G[vertex]) que.push(i);
  while(!(que.empty()))
  {
    int next = que.front();
    que.pop();
    if (seen[next] == false)
    {
      bfs(next,depth + 1);
    }
  }

  
}




int main()
{
  fill_n(ans,105,-1);
  fill_n(seen,105,false);
  int n;cin>>n;
  for (int i = 0; i < n; i++)
  {
    int u;cin>>u;
    int k;cin>>k;
    for (int j = 0; j < k; j++)
    {
      int v;cin>>v;
      G[u].push_back(v);
    }
    
  }

}
*/



  
int ans[105];
vector<int> G[105];
queue<int> que;

int main()
{
  fill_n(ans,105,-1);
  int n;cin>>n;
  for (int i = 0; i < n; i++)
  {
    int u;cin>>u;
    int k;cin>>k;
    for (int j = 0; j < k; j++)
    {
      int v;cin>>v;
      G[u].push_back(v);
    }
    
  }


/*
  for (int i = 1; i <= n; i++)
  {
    cout << i << ": " ;
    for (auto &&j : G[i])
    {
      cout << j << " ";
    }
    cout << endl;
    
  }
*/


  que.push(1);
  ans[1] = 0;

  while (!que.empty())
  {
    int vertex = que.front();
    que.pop();

    for (auto &&next : G[vertex])
    {
      if (ans[next] != -1) continue;
      que.push(next);
      ans[next] = ans[vertex] + 1;
    }
  

  }
  

  for (int i = 1; i <= n; i++)
  {
    cout << i << " " << ans[i] << endl;
  }
  

}

C++: // -*- mode:c++; coding:utf-8; c-basic-offset:2; -*-
// ALDS1_11_C: Breadth First Search

#include <algorithm>
#include <cstdio>
#include <queue>

using uint = unsigned int;

class Graph {
  const uint n_;
  uint* const g_;
  int* const depth_;
  
public:
  Graph(uint n) : n_(n),
                  g_(new uint[(n_*n_)]),
                  depth_(new int[n])
  {
    std::fill(g_, g_+(n_*n_), 0u);
  }

  ~Graph()
  {
    delete[] g_;
    delete[] depth_;
  }
  
  uint* operator [](uint i) const { return g_+(n_*i); }

  int* depth() const { return depth_; }

  void bfs()
  {
    init_depth();
    std::queue<uint> q;
    auto i = 0u;
    q.push(i);
    depth_[i] = 0;
    while (!q.empty()) {
      i = q.front();
      for (auto j = 0u; j < n_; ++j) {
        if ((*this)[i][j] && depth_[j] == -1) {
          q.push(j);
          depth_[j] = depth_[i]+1;
        }
      }
      q.pop();
    }
  }

private:
  void init_depth()
  {
    std::fill(depth_, depth_+(n_), -1);
  }
};

int main()
{
  uint n;
  std::scanf("%u", &n);

  Graph g(n);

  uint u, k, v;
  for (auto i = 0u; i < n; ++i) {
    std::scanf("%u %u", &u, &k);
    for (auto j = 0u; j < k; ++j) {
      std::scanf("%u", &v);
      g[u-1][v-1] = 1;
    }
  }

  g.bfs();
  auto depth = g.depth();
  for (auto i = 0u; i < n; ++i) {
    std::printf("%u %d\n", i+1, depth[i]);
  }
}

// eof

C++: #include<iostream>
#include<queue>

using namespace std;

static const int N = 100;

int n,d[N],M[N][N];//d[]...?§??????????????????¢(-1?????°?????????)???M[][]?????£??\???????????§????????????

void dfs(int r) {
	queue<int> q;//queue??§?????????
	q.push(r);//?§?????????£??\
	for (int i = 0; i < n; i++) d[i] = -1;//??????????????????
	d[r] = 0;//?§????????????¢???0

	int u;
	while (!q.empty()) {//??¢?´¢???????????§??°?????????
		u = q.front();//u????????\?????????????????¢?´¢???????????£?????????????????£??\
		q.pop();//?????\???????????????????´????????????????

		for (int v = 0; v < n; v++) {//??£??\????????????????????????
			if (M[u][v] == 0) continue;//?§??????¨??????????????§?????°?????????????????´???????????????
			if (d[v] != -1) continue;//?§??????¨????????¢???????????£??????????????¢?´¢???????????£??????????????´??????????????????
			d[v] = d[u] + 1;//??????u????§??????¨??£??\?????????????????????????????¢1???1?????????????????????????????????+1???
			q.push(v);//?????\??????v?????????
		}
	}
	for (int i = 0; i < n; i++) {
		cout<<i+1<<" "<<d[i]<<endl;//??????
	}
}

int main() {
	int u, p, v;
	cin >> n;
	for (int i = 0; i < n; i++) {//?????????(d[]?????¢????????????dfs??§?±??????????????????§????????????????????????)
		for (int j = 0; j < n; j++) {
			M[i][j] = 0;
		}
	}

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

	dfs(0);//??????0????§??????¨??????

	return 0;
}