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;
typedef long long ll;
#define REP(i,n) for(int i=0; i<(n); i++)
#define REP2(i,x,n) for(int i=x; i<(n); i++)
#define PRINT(x) cout<<(x)<<endl
#define INF 1000000000000 // 10^12
#define MOD 1000000007 // 10^9+7
#define PB push_back
#define MP make_pair

const int MAX_N = 100;

int n, u, k, v;

vector<int> G[MAX_N];
int d[MAX_N]; // distance from 0

int main() {
    // input
    cin >> n;
    REP(i, n) {
        cin >> u >> k;
        REP(j, k) {
            cin >> v;
            G[u-1].PB(v-1);
        }
    }

    // init d
    REP(i, n) d[i] = -1;

    // BFS
    queue<int> Q;
    Q.push(0);
    d[0] = 0;
    while (Q.size()) {
        int pos = Q.front(); Q.pop();
        REP(i, G[pos].size()) {
            int to = G[pos][i];
            if (d[to] != -1) continue;
            Q.push(to);
            d[to] = d[pos] + 1;
        }
    }

    // output
    REP(i, n) {
        int id = i + 1;
        printf("%d %d\n", id, d[i]);
    }

    return 0;
}

C++: #include <bits/stdc++.h>
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define rep1(i, n) for (int i = 1; i < (n); ++i)
using namespace std;
typedef long long ll;

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

    int n;
    cin >> n;

    vector<vector<int>> g(n);
    rep(i, n){
        int u, k;
        cin >> u >> k;
        --u;

        rep(j, k){
            int v;
            cin >> v;
            --v;

            g[u].push_back(v);
        }
    }

    queue<int> q;
    vector<int> dist(n, -1);
    q.push(0);
    dist[0] = 0;
    while(!q.empty()){
        int v = q.front();
        q.pop();
        
        for(int nv : g[v]){
            if(dist[nv] != -1) continue;

            dist[nv] = dist[v] + 1;
            q.push(nv);
        }
    }

    rep(i, n) cout << i+1 << " " << dist[i] << endl;

    return 0;
}

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