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

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

C++: 
#if 1
#include <iostream>
#include <fstream>
#include <string>
#include <vector>
#include <map>
#include <set>
#include <unordered_map>
#include <unordered_set>
#include <queue>
#include <stack>
#include <array>
#include <deque>
#include <algorithm>
#include <utility>
#include <cstdint>
#include <functional>
#include <iomanip>
#include <numeric>
#include <assert.h>
#include <bitset>
#include <list>

auto& in = std::cin;
auto& out = std::cout;
#define all_range(C) std::begin(C), std::end(C)
const double PI = 3.141592653589793238462643383279502884197169399375105820974944;

namespace std {
	template<class Ty, size_t Ix>
	struct rank<std::array<Ty,Ix>>
		: integral_constant<size_t, rank<Ty>::value + 1>
	{	// determine number of dimensions of array _Ty
	};
}

template<typename T, typename U>
std::enable_if_t<std::rank<T>::value == 0> fill_all(T& arr, const U& v) {
	arr = v;
}
template<typename ARR, typename U>
std::enable_if_t<std::rank<ARR>::value != 0> fill_all(ARR& arr, const U& v) {
	for (auto& i : arr) {
		fill_all(i, v);
	}
}

int32_t N;
int32_t INF = 100100;
std::array<std::array<int32_t, 100>,100> dp;
std::array<std::array<int32_t, 100>, 100> dp2;
void WF() {
	for (size_t k = 0; k < N; k++)
		for (size_t i = 0; i < N; i++)
			for (size_t j = 0; j < N; j++)
	{
		dp[i][j] = std::min(dp[i][j], dp[i][k] + dp[k][j]);
	}
}

int main()
{
	using std::endl;
	in.sync_with_stdio(false);
	out.sync_with_stdio(false);
	in.tie(nullptr);
	out.tie(nullptr);

	fill_all(dp, INF);
	in >> N;
	for (int32_t i = 0; i < N; i++)
	{
		int from,m;
		in >> from >> m; --from;
		dp[from][from] = 0;
		for (int32_t j = 0; j < m; j++)
		{
			int to;
			in >> to; --to;
			dp[from][to] = 1;
		}
	}

	WF();
	dp2 = dp;
	WF();
		for (int32_t i = 0; i < N; i++)
		{
			out << i + 1 << ' ' << (dp[0][i]!=INF? dp[0][i]:-1) << endl;
		}

	return 0;
}
#endif

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

using namespace std;
#define MAX 100

const int INF = (1<<21);
int mat[MAX][MAX] = {};
int n, d[MAX] = {};
bool c[MAX];

void bfs(int u){
    queue<int> p; 
    int now = 0;
    d[u] = now++;
    c[u] = true;

    p.push(u);
    while(!p.empty()){
        int x = p.front(); p.pop();
        for(int i = 0; i < n; i++){
            if(mat[x][i] && !c[i]){
                p.push(i);
                c[i] = true;
                d[i] = d[x]+1;
            }
        }
    }
}

int main(){
    cin >> n;
    
    for(int i = 0; i < n; i++){
        int x, k, y;
        cin >> x >> k;
        while(k-- > 0){
            cin >> y;
            mat[x-1][y-1] = 1;
        }
    }

    memset(d, INF, MAX);
    bfs(0);

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

C++: #include <bits/stdc++.h>
#define all(v) v.begin(), v.end()
#define rall(v) v.rbegin(), v.rend()
#define rep(i,n) for (int i=0;i<(int)(n);i++)
#define codefor int test;scanf("%d",&test);while(test--)
#define INT(...) int __VA_ARGS__;in(__VA_ARGS__)
#define LL(...) ll __VA_ARGS__;in(__VA_ARGS__)
#define yn(ans) if(ans)printf("Yes\n");else printf("No\n")
#define YN(ans) if(ans)printf("YES\n");else printf("NO\n")
#define vector2d(type,name,h,...) vector<vector<type>>name(h,vector<type>(__VA_ARGS__))
#define umap unordered_map
#define uset unordered_set
using namespace std;
using ll = long long;
const int MOD=1000000007;
//入力系
void scan(int& a){scanf("%d",&a);}
void scan(long long& a){scanf("%lld",&a);}
template<class T> void scan(T& a){cin>>a;}
template<class T> void scan(vector<T>& vec){for(auto&& it:vec)scan(it);}
void in(){}
template <class Head, class... Tail> void in(Head& head, Tail&... tail){scan(head);in(tail...);}
//出力系
void print(const int& a){printf("%d",a);}
void print(const long long& a){printf("%lld",a);}
void print(const double& a){printf("%.15lf",a);}
template<class T> void print(const T& a){cout<<a;}
template<class T> void print(const vector<T>& vec){if(vec.empty())return;print(vec[0]);for(auto it=vec.begin();++it!= vec.end();){putchar(' ');print(*it);}}
void out(){putchar('\n');}
template<class T> void out(const T& t){print(t);putchar('\n');}
template <class Head, class... Tail> void out(const Head& head,const Tail&... tail){print(head);putchar(' ');out(tail...);}
//デバッグ系
template<class T> void dprint(const T& a){cerr<<a;}
template<class T> void dprint(const vector<T>& vec){if(vec.empty())return;cerr<<vec[0];for(auto it=vec.begin();++it!= vec.end();){cerr<<" "<<*it;}}
void debug(){cerr<<endl;}
template<class T> void debug(const T& t){dprint(t);cerr<<endl;}
template <class Head, class... Tail> void debug(const Head& head, const Tail&... tail){dprint(head);cerr<<" ";debug(tail...);}

int main(){
    INT(n);
    vector<vector<int>> graph(n);
    rep(i,n){
        INT(x,y);
        rep(j,y){
            INT(z);
            graph[x-1].push_back(z-1);
        }
    }
    queue<int> Q;
    vector<int> checked(n,-1);
    Q.push(0);
    checked[0]=0;
    while(!Q.empty()){
        int x=Q.front();
        Q.pop();
        rep(i,graph[x].size()){
            if(checked[graph[x][i]]==-1){
                checked[graph[x][i]]=checked[x]+1;
                Q.push(graph[x][i]);
            }
        }
    }
    rep(i,n)out(i+1,checked[i]);
}