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 <iostream>
#include <queue>

using namespace std;
const int N=100;
const int INFTY=(1<<21);

int n,M[N][N];
//??????????????????????????¶??????color???
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=0;
    while(!q.empty()){
        u=q.front();q.pop();
        for(int v=0;v<n;v++)
            if(M[u][v]!=0&&d[v]==INFTY){
                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);
}

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

//#define int long long
typedef long long ll;

typedef unsigned long long ul;
typedef unsigned int ui;
const ll mod = 1000000007;
const ll INF = mod * mod;
const int INF_N = 1e+9;
typedef pair<int, int> P;
#define stop char nyaa;cin>>nyaa;
#define rep(i,n) for(int i=0;i<n;i++)
#define per(i,n) for(int i=n-1;i>=0;i--)
#define Rep(i,sta,n) for(int i=sta;i<n;i++)
#define rep1(i,n) for(int i=1;i<=n;i++)
#define per1(i,n) for(int i=n;i>=1;i--)
#define Rep1(i,sta,n) for(int i=sta;i<=n;i++)
#define all(v) (v).begin(),(v).end()
typedef pair<ll, ll> LP;
typedef long double ld;
typedef pair<ld, ld> LDP;
const ld eps = 1e-12;
const ld pi = acos(-1.0);
//typedef vector<vector<ll>> mat;
typedef vector<int> vec;

//繰り返し二乗法
ll mod_pow(ll a, ll n, ll m) {
	ll res = 1;
	while (n) {
		if (n & 1)res = res * a%m;
		a = a * a%m; n >>= 1;
	}
	return res;
}

struct modint {
	ll n;
	modint() :n(0) { ; }
	modint(ll m) :n(m) {
		if (n >= mod)n %= mod;
		else if (n < 0)n = (n%mod + mod) % mod;
	}
	operator int() { return n; }
};
bool operator==(modint a, modint b) { return a.n == b.n; }
modint operator+=(modint &a, modint b) { a.n += b.n; if (a.n >= mod)a.n -= mod; return a; }
modint operator-=(modint &a, modint b) { a.n -= b.n; if (a.n < 0)a.n += mod; return a; }
modint operator*=(modint &a, modint b) { a.n = ((ll)a.n*b.n) % mod; return a; }
modint operator+(modint a, modint b) { return a += b; }
modint operator-(modint a, modint b) { return a -= b; }
modint operator*(modint a, modint b) { return a *= b; }
modint operator^(modint a, int n) {
	if (n == 0)return modint(1);
	modint res = (a*a) ^ (n / 2);
	if (n % 2)res = res * a;
	return res;
}

//逆元(Eucledean algorithm)
ll inv(ll a, ll p) {
	return (a == 1 ? 1 : (1 - p * inv(p%a, a)) / a + p);
}
modint operator/(modint a, modint b) { return a * modint(inv(b, mod)); }

const int max_n = 1 << 18;
modint fact[max_n], factinv[max_n];
void init_f() {
	fact[0] = modint(1);
	for (int i = 0; i < max_n - 1; i++) {
		fact[i + 1] = fact[i] * modint(i + 1);
	}
	factinv[max_n - 1] = modint(1) / fact[max_n - 1];
	for (int i = max_n - 2; i >= 0; i--) {
		factinv[i] = factinv[i + 1] * modint(i + 1);
	}
}
modint comb(int a, int b) {
	if (a < 0 || b < 0 || a < b)return 0;
	return fact[a] * factinv[b] * factinv[a - b];
}
using mP = pair<modint, modint>;

int dx[4] = { 0,1,0,-1 };
int dy[4] = { 1,0,-1,0 };


struct Object {
    // 任意の構造体
    ll x;
    ll depth;
};

queue<Object> q;
vector<vec> v;
int n;
vector<int> d;

void bfs() {
    while (!q.empty()) {
        // キューの先頭の要素を取り出す dequeue(pop)
        Object now = q.front(); q.pop();
        
        // 停止条件
        // if (now.hoge == target) return ~;  // 探索対象
        // if (now.x == gx && now.y == gy) return now.depth;
        
        // BFS
        rep(i, v[now.x].size()){
            ll next_x = v[now.x][i];
            if(d[next_x] >= 0) continue;
            Object next = {next_x, now.depth+1};  // 深さ（ステップ数）を一つ足す
            d[next_x] = next.depth;
            q.push(next);
        }
    }
}

void solve() {
    cin >> n;
    v.resize(n);
    d.resize(n, -1);
    rep(i, n){
        int a, b; cin >> a >> b;
        a--;
        rep(j, b){
            int c; cin >> c;
            c--;
            v[a].push_back(c);
        }
    }

    d[0] = 0;
    q.push({0, 0});
    bfs();

    rep(i, n){
        cout << i+1 << " " << d[i] << endl;
    }
}

signed main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  //cout << fixed << setprecision(10);
  //init_f();
  //init();
  //int t; cin >> t; rep(i, t)solve();
  solve();
//   stop
    return 0;
}

C++: #include <iostream>
#include <vector>
#include <string>
#include <stack>
#include <queue>
#include <deque>
#include <set>
#include <map>
#include <algorithm>	// require sort next_permutation count __gcd reverse etc.
#include <cstdlib>	// require abs exit atof atoi 
#include <cstdio>		// require scanf printf
#include <functional>
#include <numeric>	// require accumulate
#include <cmath>		// require fabs
#include <climits>
#include <limits>
#include <cfloat>
#include <iomanip>	// require setw
#include <sstream>	// require stringstream 
#include <cstring>	// require memset
#include <cctype>		// require tolower, toupper
#include <fstream>	// require freopen
#include <ctime>		// require srand
#define rep(i,n) for(int i=0;i<(n);i++)
#define ALL(A) A.begin(), A.end()
#define NIL -1

using namespace std;

struct node{
	int id;
	int d;
};

node v[105];
bool vis[105];
vector<int> g[105];

void bfs (int u )
{
	vis[u] = true;
	v[u].d = 0;
	queue<node> que;
	que.push (v[u] );
	
	while (!que.empty() ){
		node cur = que.front(); que.pop();
		int id = cur.id;
		int d  = cur.d;
		rep (j, g[id].size() ){
			int next = g[id][j];
			if (!vis[next] ){
				vis[next] = true;
				v[next].d = d + 1;
				que.push (v[next] );
			} // end if
		} // end rep
	} // end while				
}

int main()
{
	memset (vis, false, sizeof (vis ) );
	ios_base::sync_with_stdio(0);
	int n; cin >> n;
	rep (i, n+1 ) g[i].clear();
	rep (i, n+1 ) v[i].id = i, v[i].d = NIL;

	rep (i, n ){
		int id; cin >> id;
		int k; cin >> k;
		while (k-- ){
			int v; cin >> v;
			g[id].push_back (v );
		} // end while
	} // end rep

	bfs (1 );

	for (int i = 1; i <= n; i++ ){
		cout << v[i].id << ' ' << v[i].d << endl;
	} // end for
		
	return 0;
}