Go: package main

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
)

// I/O
type Scanner struct {
	sc *bufio.Scanner
}

func NewScanner() *Scanner {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)
	sc.Buffer(make([]byte, 1024), int(1e+9))
	return &Scanner{sc}
}

func (s *Scanner) nextStr() string {
	s.sc.Scan()
	return s.sc.Text()
}

func (s *Scanner) nextInt() int {
	i, e := strconv.Atoi(s.nextStr())
	if e != nil {
		panic(e)
	}
	return i
}

func (s *Scanner) nextFloat() float64 {
	f, e := strconv.ParseFloat(s.nextStr(), 64)
	if e != nil {
		panic(e)
	}
	return f
}

func (s *Scanner) nextRuneSlice() []rune {
	return []rune(s.nextStr())
}

func (s *Scanner) nextIntSlice(n int) []int {
	res := make([]int, n)
	for i := 0; i < n; i++ {
		res[i] = s.nextInt()
	}
	return res
}

func (s *Scanner) nextFloatSlice(n int) []float64 {
	res := make([]float64, n)
	for i := 0; i < n; i++ {
		res[i] = s.nextFloat()
	}
	return res
}

// Arithmetic
func max(nums ...int) int {
	m := nums[0]
	for _, i := range nums {
		if m < i {
			m = i
		}
	}
	return m
}

func min(nums ...int) int {
	m := nums[0]
	for _, i := range nums {
		if m > i {
			m = i
		}
	}
	return m
}

func abs(x int) int {
	if x > 0 {
		return x
	}
	return -x
}

func pow(x, y int) int {
	res := 1
	for i := 0; i < y; i++ {
		res *= x
	}
	return res
}

func ceil(a, b int) int {
	if a%b == 0 {
		return a / b
	} else {
		return a/b + 1
	}
}

// Sort
type RuneSlice []rune

func (a RuneSlice) Len() int           { return len(a) }
func (a RuneSlice) Less(i, j int) bool { return a[i] < a[j] }
func (a RuneSlice) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }

// Main
type Queue struct {
	arr []int
}

func (q *Queue) push(v int) {
	q.arr = append(q.arr, v)
}

func (q *Queue) pop() int {
	res := q.arr[0]
	q.arr = q.arr[1:]
	return res
}

func (q *Queue) isEmpty() bool {
	return len(q.arr) == 0
}

func main() {
	sc := NewScanner()
	wtr := bufio.NewWriter(os.Stdout)
	N := sc.nextInt()
	G := make([][]int, N)
	for i := 0; i < N; i++ {
		u, k := sc.nextInt()-1, sc.nextInt()
		for j := 0; j < k; j++ {
			G[u] = append(G[u], sc.nextInt()-1)
		}
	}
	var q Queue
	seen := make([]int, N)
	for i := 0; i < N; i++ {
		seen[i] = -1
	}
	var search func(cur int)
	search = func(cur int) {
		for i := 0; i < len(G[cur]); i++ {
			next := G[cur][i]
			if seen[next] == -1 {
				q.push(next)
				seen[next] = seen[cur] + 1
			}
		}
	}
	q.push(0)
	seen[0] = 0
	for !q.isEmpty() {
		search(q.pop())
	}

	for i := 0; i < N; i++ {
		fmt.Fprintln(wtr, i+1, seen[i])
	}
	wtr.Flush()
}

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

#define rep(i, n) for (int i=0; i<(n); ++i)
using ll = long long;
using P = pair<int, int>;

const int WHITE = 0;
const int GRAY = 1;
const int BLACK = 2;
const int MAX = 103;
const int INF = -1;
int G[MAX][MAX];
int n;
int color[MAX], dist[MAX];

void bfs(int s) {
  memset(color, WHITE, sizeof(color));
  memset(dist, INF, sizeof(dist));

  queue<int> Q;

  color[s] = GRAY;
  dist[s] = 0;
  Q.push(s);

  while (!Q.empty()) {
    int u = Q.front(); Q.pop();
    rep(v,n) {
      if (G[u][v] && color[v] == WHITE) {
	color[v] = GRAY;
	dist[v] = dist[u] + 1;
	Q.push(v);
      }
    }
    color[u] = BLACK;
  }
}

int main() {
  cin >> n;
  rep(i,n) memset(G[i], 0, sizeof(G[i])); // init
  int u, k;
  rep(i,n) {
    cin >> u >> k;
    rep(j,k) {
      int t;
      cin >> t;
      G[i][t-1] = 1;
    }
  }

  bfs(0);

  rep(i,n) {
    cout << i+1 << ' ' << (dist[i]==INF ? -1 : dist[i]) << endl;
  }
  return 0;
}

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

int d[110];

int main() {
  int n;
  std::cin >> n;
  int G[110][110];
  for(int i=0; i<n; ++i) {
    for(int j=0; j<n; ++j) G[i][j] = 0;
  }

  for(int i=0; i<n; ++i) {
    d[i] = -1;
  }

  for(int i=0; i<n; ++i) {
    int u, k;
    std::cin >> u >> k;
    u--;
    for(int j=0; j<k; ++j) {
      int v;
      std::cin >> v;
      v--;
      G[u][v] = 1;
    }
  }

  std::queue<int> que;
  que.push(0);
  int dist = 0;
  d[0] = 0;

  while(!que.empty()) {
    // キューから一番最初を取り出す
    int u = que.front();
    que.pop();

    for(int v=0; v<n; ++v) {
      if(G[u][v] == 1 && d[v] == -1) {
        que.push(v);
        d[v] = d[u]+1;
      }
    }
  }

  for(int i=0; i<n; ++i) {
    std::cout << i+1 << " " << d[i] << std::endl;
  }
}

C++: #define _USE_MATH_DEFINES
#include<iostream>
#include<algorithm>
#include<string>
#include<iomanip>
#include<cmath>
#include<vector>
#include<deque>
#include<queue>
#include<map>
#include<set>
#define ll long long
#define vec vector
#define vll vec<ll>
#define dou(s) atof(s.c_str())
#define lon(s) atoll(s.c_str())
#define str(n) to_string(n)
#define rep(i,a,b) for(ll i=a;i<b;i++)
#define rrep(i,b,a) for(ll i=b;i>=a;i--)
#define ALL(a) a.begin(),a.end()
#define rALL(a) a.rbegin(),a.rend()
#define line "\n"
#define mav(a) (*max_element(ALL(a)))
#define miv(a) (*min_element(ALL(a)))
#define vfind(a,n) (find(ALL(a),n)-a.begin())
#define prque priority_queue
#define MOD 1000000007ll
using namespace std;
void solve();
int main() {
	cin.tie(0);
	ios::sync_with_stdio(false);
	solve();
}

//nCk(mod p)
/*ll fac[510000], finv[510000], inv[510000];
void cmodf(ll p = MOD) {
	fac[0] = fac[1] = 1;
	finv[0] = finv[1] = 1;
	inv[1] = 1;
	rep(i, 2, 510000) {
		fac[i] = fac[i - 1] * i%p;
		inv[i] = p - inv[p%i] * (p / i) % p;
		finv[i] = finv[i - 1] * inv[i] % p;
	}
}
ll cmod(ll n, ll k, ll p = MOD) {
	return fac[n] * (finv[k] * finv[n - k] % p) % p;
}*/

//最大公約数
ll gcd(ll n, ll m) {
	ll k = n % m;
	while (k != 0) { n = m; m = k; k = n % m; }
	return m;
}
ll gcd(vector<ll> a) {
	rep(i, 1, a.size()) {
		ll k = a[i - 1] % a[i];
		while (k != 0) {
			a[i - 1] = a[i];
			a[i] = k;
			k = a[i - 1] % a[i];
		}
	}
	return a.back();
}

//最小公倍数
ll lcm(ll n, ll m) {
	ll t = n * m, k = n % m;
	while (k != 0) { n = m; m = k; k = n % m; }
	return t / m;
}
ll lcm(vector<ll> a) {
	ll n;
	rep(i, 1, a.size()) {
		n = a[i - 1] * a[i];
		ll k = a[i - 1] % a[i];
		while (k != 0) {
			a[i - 1] = a[i];
			a[i] = k;
			k = a[i - 1] % a[i];
		}
		n /= a[i];
		a[i] = n;
	}
	return n;
}

//keyの小さい方から探していった時に初めてvalueがjoken以上になる時のkey（keyが増えたらvalueも増えるか同じになるとき）
ll value(ll key) {
	/*変更*/
	return 0;
}
ll mini(ll lkey, ll rkey/*ここも調べる*/, ll joken) {
	ll mkey;
	while (lkey != rkey) {
		mkey = (lkey + rkey) / 2;
		if (value(mkey) >= joken)rkey = mkey;
		else lkey = mkey + 1;
	}
	return rkey;
}

//ペア配列の整理
struct cpl {
	ll f, s;
	bool operator<(const cpl &c) const {
		return f != c.f ? f < c.f : s < c.s;
	};
};

//変数定義
ll n; vec<vll> a, c; vll le;
//再帰関数
void f(ll i, ll l) {
	rep(j, 0, n) {
		if (a[i][j] == 1) {
			c[l].push_back(j);
			le[j] = l + 1;
		}
	}
}
bool g(ll i) {
	if (c[i].size() == 0)return false;
	rep(j, 0, c[i].size()) {
		rep(k, 0, n) {
			a[k][c[i][j]] = 0;
		}
	}
	return true;
}
//アルゴリズム
void solve() {
	cin >> n;
	a.resize(n, vll(n, 0));
	rep(i, 0, n) {
		ll k, m; cin >> k >> m;
		rep(j, 0, m) {
			ll l; cin >> l;
			a[k - 1][l - 1] = 1;
		}
	}
	c.resize(n);
	le.resize(n, -1);
	le[0] = 0;
	rep(i, 0, n)a[i][0] = 0;
	ll l = 0;
	f(0, l);
	while (g(l)) {
		rep(i, 0, c[l].size())f(c[l][i], l + 1);
		l++;
	}
	rep(i, 0, n)cout << i + 1 << " " << le[i] << line;
}