Go: package main

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

type AdjacentList struct {
	matrix [][]int
}

func NewEmptyAdjacentList(dim int) *AdjacentList {
	matrix := make([][]int, dim)
	for i := 0; i < dim; i++ {
		matrix[i] = make([]int, dim)
	}
	return &AdjacentList{matrix: matrix}
}

func (al *AdjacentList) set(node int, adjacent int) {
	al.matrix[node-1][adjacent-1] = 1
}

func (al *AdjacentList) findAdjacentsFor(node int) []int {
	adjacents := []int{}
	for i, v := range al.matrix[node-1] {
		if v == 1 {
			adjacents = append(adjacents, i+1)
		}
	}
	return adjacents
}

type DistanceList struct {
	list []int
}

func NewDistanceList(dim int) *DistanceList {
	list := make([]int, dim)
	for i := 0; i < dim; i++ {
		list[i] = -1
	}
	return &DistanceList{list: list}
}

func (dl *DistanceList) set(node int, distance int) {
	dl.list[node-1] = distance
}

func (dl *DistanceList) get(node int) int {
	return dl.list[node-1]
}

func (dl *DistanceList) isVisited(node int) bool {
	return dl.list[node-1] >= 0
}

type Position struct {
	node     int
	distance int
}

func main() {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)

	dim, err := nextInt(sc)
	if err != nil {
		panic(err)
	}

	al := NewEmptyAdjacentList(dim)

	for i := 1; i <= dim; i++ {
		node, err := nextInt(sc)
		if err != nil {
			panic(err)
		}

		adjacentNum, err := nextInt(sc)
		if err != nil {
			panic(err)
		}
		for j := 0; j < adjacentNum; j++ {
			adjacent, err := nextInt(sc)
			if err != nil {
				panic(err)
			}
			al.set(node, adjacent)
		}
	}

	dl := NewDistanceList(dim)

	bfs(al, dl)

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

func bfs(al *AdjacentList, dl *DistanceList) {
	stack := []Position{Position{node: 1, distance: 0}}
	for len(stack) > 0 {
		currentPosition := stack[0]
		stack = stack[1:]
		if !dl.isVisited(currentPosition.node) {
			dl.set(currentPosition.node, currentPosition.distance)
		}
		for _, v := range al.findAdjacentsFor(currentPosition.node) {
			if !dl.isVisited(v) {
				stack = append(stack, Position{node: v, distance: currentPosition.distance + 1})
			}
		}
	}
}

func nextInt(sc *bufio.Scanner) (int, error) {
	sc.Scan()
	return strconv.Atoi(sc.Text())
}

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

using namespace std;

#define FOR(i, a, b) for(ll i = (a); i < (b); ++i)
#define FORR(i, a, b) for(ll i = (a); i > (b); --i)
#define REP(i, n) for(ll i = 0; i < (n); ++i)
#define REPR(i, n) for(ll i = n; i >= 0; i--)
#define FOREACH(x, a) for(auto &(x) : (a))
#define VECCIN(x)                                                              \
    for(auto &youso_ : (x)) cin >> youso_
#define mp make_pair
#define bitcnt __builtin_popcount
#define SZ(x) ((ll)(x).size())
#define All(a) (a).begin(), (a).end()
template <typename T = long long> inline T IN() {
    T x;
    cin >> x;
    return (x);
}
inline void CIN() {}
template <class Head, class... Tail>
inline void CIN(Head &&head, Tail &&... tail) {
    cin >> head;
    CIN(move(tail)...);
}
#define CINT(...)                                                              \
    int __VA_ARGS__;                                                           \
    CIN(__VA_ARGS__)
#define LCIN(...)                                                              \
    ll __VA_ARGS__;                                                            \
    CIN(__VA_ARGS__)
#define SCIN(...)                                                              \
    string __VA_ARGS__;                                                        \
    CIN(__VA_ARGS__)
#define Yes(a) cout << (a ? "Yes" : "No") << "\n"
#define YES(a) cout << (a ? "YES" : "NO") << "\n"

typedef long long ll;
typedef unsigned long long ul;
typedef vector<int> V;
typedef vector<ll> VL;
typedef pair<ll, ll> PL;
typedef priority_queue<ll> PQ;
typedef priority_queue<ll, V, greater<ll>> PQG;

const int INF = 1e9;
const int MOD = 1e9 + 7;
// const int MOD = 998244353;
const ll LINF = 1e18;

ll N, M;
vector<VL> G;
vector<bool> went;
VL d;

signed main() {
    cin >> N;
    G.resize(N);
    d.resize(N, LINF);
    REP(i, N) {
        LCIN(u, k);
        REP(i, k) { G[u - 1].emplace_back(IN() - 1); }
    }
    queue<ll> q;
    q.emplace(0);
    d[0] = 0;
    while(!q.empty()) {
        ll now = q.front();
        q.pop();
        FOREACH(to, G[now]) {
            if(d[to] > d[now] + 1) {
                d[to] = d[now] + 1;
                q.emplace(to);
            }
        }
    }
    REP(i, N) { cout << i + 1 << " " << (d[i] == LINF ? -1 : d[i]) << "\n"; }
    return 0;
}

C++: #include<iostream>
#include<string>
#include<vector>
#include<iomanip>
#include<algorithm>
#include<queue>
#include<stack>
#include<list>
#include<map>
#include<deque>
#include<math.h>
using namespace std;
#define ll long long
bool visited[111];
ll d[111];
queue< ll > que;
vector <ll> G[111];
int main(){
    ll N;
    cin >> N;
    ll i,j;
    ll u,k,v;
    for(i=0;i<N;i++){
        cin >> u >> k;
        for(j=0;j<k;j++){
            cin >> v;
            G[u-1].push_back(v-1);
        }
        d[i]=-1;
        visited[i]=0;
    }
    que.push(0);
    visited[0]=1;
    d[0]=0;
    while(!que.empty()){
        v=que.front();
        que.pop();
        for(vector<ll>::iterator itr=G[v].begin();itr!=G[v].end();++itr){
            if(visited[*itr]==0){
                que.push(*itr);
                visited[*itr]=1;
                d[*itr]=d[v]+1;
            }
        }
    }
    for(i=0;i<N;i++){
        cout <<i+1 << " " <<d[i] <<endl;
    }
    return 0;
}

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

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

int M[N][N] = {0}, d[N], n;

void bfs() {
  int u, v;
  queue<int> q;
  d[0] = 0;
  q.push(0);
  while (!q.empty()) {
    u = q.front();
    for (v = 0; v < n; v++) {
      if (M[u][v] == 0) continue;
      if (d[v] == 0) {
        q.push(v);
        d[v] = d[u] + 1;
      }
    }
    q.pop();
  }
  for (u = 0; u < n; u++) {
    cout << u + 1 << ' ' << d[u] << endl;
  }
}

int main() {
  int u, v, k, i, j;

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

  bfs();

  return 0;
}

C++: #define _USE_MATH_DEFINES
#include "bits/stdc++.h"
using namespace std;

//#define int long long
#define DBG 1
#define dump(o) if(DBG){cerr<<#o<<" "<<o<<endl;}
#define dumpc(o) if(DBG){cerr<<#o; for(auto &e:(o))cerr<<" "<<e;cerr<<endl;}
#define rep(i,a,b) for(int i=(a);i<(b);i++)
#define rrep(i,a,b) for(int i=(b)-1;i>=(a);i--)
#define each(it,c) for(auto it=(c).begin();it!=(c).end();it++)
#define all(c) c.begin(),c.end()
const int INF = sizeof(int) == sizeof(long long) ? 0x3f3f3f3f3f3f3f3fLL : 0x3f3f3f3f;
const int MOD = (int)(1e9 + 7);
vector<vector<int> >vec;
int n;
vector<int>d;
void bfs(int s) {
	queue<int>q;
	q.push(s);
	d[s] = 0;
	while (!q.empty()) {
		int u = q.front(); q.pop();
		rep(v, 0, vec[u].size()) {
			if (d[vec[u][v]] != INF)continue;
			d[vec[u][v]] = d[u] + 1;
			q.push(vec[u][v]);
		}
	}
	rep(i, 0, n) {
		cout << i + 1 << " " << ((d[i]==INF)?-1:d[i]) << endl;
	}
}
signed main() {
	cin >> n; vec = vector<vector<int> >(n); d = vector<int>(n, INF);
	rep(i, 0, n) {
		int u, k; cin >> u >> k; u--;
		rep(j, 0, k) {
			int v; cin >> v; v--;
			vec[u].push_back(v);
		}
	}
	bfs(0);

	return 0;
}