Go: package main

import (
	"fmt"
)

func main() {
	var n int
	fmt.Scan(&n)

	g := make([][]int, n+1)
	d := make([]int, n+1)
	for i := 0; i < n; i++ {
		var u,k int
		fmt.Scan(&u)
		fmt.Scan(&k)
		g[u] = make([]int, k)
		for j := 0; j < k; j++ {
			fmt.Scan(&g[u][j])
		}

		d[i+1] = -1
	}

	q := [][]int{}
	q = append(q, []int{1, 0})
	for len(q) > 0 {
		pop := q[0]
		if len(q) > 1 {
			q = q[1:]
		} else {
			q = [][]int{}
		}
		if d[pop[0]] >= 0 {
			continue
		}
		d[pop[0]] = pop[1]

		for j := 0; j < len(g[pop[0]]); j++ {
			q = append(q, []int{g[pop[0]][j], pop[1]+1})
		}
	}

	for i := 1; i <= n; i++ {
		fmt.Printf("%d %d\n", i, d[i])
	}
}

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

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

    int n;
    cin >> n;

    vector<int> G[n];
    for(int i = 0; i < n; i++){
        int p, k;
        cin >> p >> k;
        for(int j = 0; j < k; j++){
            int a;
            cin >> a;
            G[p - 1].push_back(a - 1);
        }
    }

    vector<int> D(n, 1e9);
    D[0] = 0;
    queue<int> q;
    q.push(0);

    while(!q.empty()){
        int now = q.front();
        q.pop();

        for(int i = 0; i < G[now].size(); i++){
            int to = G[now][i];
            if(D[now] + 1 < D[to]){
                D[to] = D[now] + 1;
                q.push(to);
            }
        }
    }

    for(int i = 0; i < n; i++){
        cout << i + 1 << ' ' << (D[i] == 1e9 ? -1 : D[i]) << endl;
    }

    return 0;
}

C++: #include <bits/stdc++.h>

using namespace std;
typedef long long ll;

#define INF (long long)(1e9+7)
#define REP(i,n) for(ll i = 0; i < n; i++)
#define REP1(i,n) for(ll i = 1; i <= n; i++)

using Graph = vector<vector<int>>;


int main(void)
{
  int n;
  cin >> n;
  Graph G(n);
  int u, k;
  REP(j, n) {
    cin >> u >> k;
    u--;
    REP(i, k) {
      int v;
      cin >> v;
      v--;
      G[u].push_back(v);
      //      G[v].push_back(u);
    }
  }

  vector<int> dist(n, -1);
  queue<int> que;

  dist[0] = 0;
  que.push(0);

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

    for(int nv : G[v]) {
      if(dist[nv] != -1) continue;

      dist[nv] = dist[v] + 1;
      que.push(nv);
    }
  }
  REP(i, n) cout << i + 1 << " " << dist[i] << endl;

}

C++: #include <iostream>
#include <algorithm>
#include <string>
#include <stack>
#include <cstdlib>
#include <queue>
#include <vector>
#include <set>

using namespace std;
int n,m,l,p;
bool a[100][100];
int D[100];
void bfs( int src) {
	queue<int> Q;
	Q.push(src);
	D[src]=0;
	while( ! Q.empty() ) {
		int cur = Q.front();
		Q.pop();
		for(int dst = 0; dst < n; dst++ ) {
			if( D[dst] == 0 && a[cur][dst] == 1 ) {
				D[dst] = D[cur] + 1;
				Q.push(dst);
			}
		}
	}
	for (int i = 0; i < n;i++) {
	cerr << i+1 <<  " " << D[i] <<  endl;
	}
}

int main() {
	cin >> n;
	for ( int i = 0;i < n;i++) {
		D[i] = 0;
		for(int j= 0; j < n;j++) {
			a[i][j] = 0;
		}
	}
	for (int i = 0;i < n; i++){
		cin >> m;
		cin >> l;
		for(int j = 0; j < l;j++) {
			cin >> p;
			a[m-1][p-1] = 1;
		}
	}
	bfs(0);
}

C++: #pragma GCC diagnostic ignored "-Wunused-variable" 
#include <bits/stdc++.h>
using namespace std;

//#define BOOST
#ifdef BOOST
#include <boost/multiprecision/cpp_int.hpp>
#include <boost/multiprecision/cpp_dec_float.hpp>
#include <boost/range/adaptor/reversed.hpp>
using namespace boost;
using ml = boost::multiprecision::cpp_int;
using md = boost::multiprecision::cpp_dec_float_100;
#define forir(i, ...) if(ll i=(ll)v.size())for(__VA_ARGS__)if(i--,1)
#define eachr(i, e, c) forir(i, auto &&e: adaptors::reverse(c))
#endif

/***** type *****/
using ll = long long;
using ld = long double;
using pll = pair<long long, long long>;
template <class T> using vt = vector<T>;
template <class T> using vvt = vector<vector<T>>;
template <class T> using vvvt = vector<vector<vector<T>>>;
/***** define *****/
#define all(c) (c).begin(), (c).end()            // begin to end
#define coutd cout << fixed << setprecision(10)  // cout double
#define output(x) do{cout<<x;return 0;}while(0)  // cout return
#define rep(i, b, e) for (ll i = b; i < e; i++)  // repeat
#define repr(i, b, e) for (ll i = b; e < i; i--) // repeat reverse
#define fori(i, ...) if (ll i = -1) for(__VA_ARGS__) if (i++, 1)
#define each(i, e, c) fori (i, auto&& e: c)      // for each
/***** const value *****/
#define llong_max 9223372036854775807            // 9 * 10^18
#define ldbl_max 1.79769e+308                    // 1.7 * 10^308
#define pi 3.1415926535897932                    // 3.14 ...
/***** lambda *****/
auto Ceil = [] // if (a % b != 0) return a / b + 1;
(auto x) { return (ll)ceil(x); };
auto Count = [] // long long count value
(auto b, auto e, auto x) { return (ll)count(b, e, x); };
auto CtoL = [] // char to number
(auto c) { return (ll)c - (ll)'0'; };
auto LtoC = [] // number to char
(auto n) { return (char)('0' + n); };
auto Pow = [] // long long pow
(auto a, auto b) { return (ll)pow(a, b); };
auto Pow2 = [] // long long pow2
(auto n) { return (1LL << n); };
auto Pow10 = [] // long long pow10
(auto n) { return (ll)pow(10, n); };
auto Size = []  // long long collection size
(auto& c) { return (ll)(c).size(); };
auto Sum = [] // long long accumulate
(auto b, auto e) { return accumulate(b, e, 0LL); };

/***** template *****/
template <class T> void MakeVVT
(ll ys, ll xs, vvt<T>& v, T fill = T())
{	// vector<vector<T>> resize + fill
	v.resize(ys); rep(y, 0, ys) v[y].resize(xs, fill);
}
template <class T> void MakeVVVT
(ll zs, ll ys, ll xs, vvvt<T>& v, T fill = T())
{	// vector<vector<vector<T>>> resize + fill
	v.resize(zs); rep(z, 0, zs) MakeVVT(ys, xs, v[z], fill);
}
template <class T> void InputVVT
(ll ys, ll xs, vvt<T>& v, T fix = T())
{	// input vector<vector<T>> (T != struct) + fix
	MakeVVT(ys, xs, v, fix);
	rep(y, 0, ys) rep(x, 0, xs) { cin >> v[y][x]; v[y][x] += fix; }
}
template <class T> void InputVVVT
(ll zs, ll ys, ll xs, vvvt<T>& v, T fix = T())
{	// input vector<vector<vector<T>>> (T != struct) + fix
	v.resize(zs); rep(z, 0, zs) InputVVT(ys, xs, v[z], fix);
}

/**************************************/
/********** BEGIN OF NYA LIB **********/
/**************************************/

namespace NyaGadget {}

namespace NyaGadget
{
	/***** BFSライブラリ *****/

	struct GT_NyaaBFS
	{
		/**
		@brief BFS実行関数
		@param start 探索開始頂点
		@param g グラフ
		@param res 結果を格納する構造体
		@note
		 探索開始頂点startからBFSで処理する。
		**/
		void Run(long long start, const std::vector<std::vector<long long>>& g, std::vector<long long>& res)
		{	// 初期化
			std::queue<long long> q;
			q.push(start);
			res.resize(g.size(), -1);
			res[start] = 0;

			while (!q.empty())
			{
				long long from = q.front(); q.pop();
				for (auto&& to : g[from])
				{	// 頂点fromから頂点toへの処理
					if (res[to] != -1) continue;
					res[to] = res[from] + 1;
					q.push(to);
				}
			}
		}

		/**
		@brief BFS実行関数
		@param start 探索開始頂点の集合
		@param g グラフ
		@param res 結果を格納する構造体
		@note
		 探索開始頂点が複数あるとき最初に全てキューに入れる必要がある。
		 したがって、開始頂点はvectorに格納して渡す。
		**/
		void Run(std::vector<long long> start, const std::vector<std::vector<long long>>& g, std::vector<long long>& res)
		{	// 初期化
			std::queue<long long> q;
			for (auto& e : start) q.push(e);
			res.resize(g.size());

			while (!q.empty())
			{
				long long from = q.front(); q.pop();
				for (auto&& to : g[from])
				{	// 頂点fromから頂点toへの処理
					q.push(to);
				}
			}
		}
	};
}

/**************************************/
/*********** END OF NYA LIB ***********/
/**************************************/

using namespace NyaGadget;
//using mll = NT_ModLL< 1000000007 >;
//using mll = NT_ModLL< 998244353 >;

int main(void)
{
	ll n; cin >> n;

	std::vector<std::vector<long long>> g(n);
	rep(i, 0, n)
	{
		ll u, k; cin >> u >> k; u--;
		rep(j, 0, k)
		{
			ll v; cin >> v; v--;
			g[u].push_back(v);
		}
	}
	GT_NyaaBFS bfs;
	std::vector<long long> res;
	bfs.Run(0, g, res);
	each(i, e, res) cout << i+1 << " " << e << endl;
	return 0;
}