Go: package main

/*
グラフの表現 隣接行列による表現
*/

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

func main() {
	scanner := makeScanner(8192)
	n := eGetInt(scanner)
	g := make([][]int, n+1)
	for i := 1; i < n+1; i++ {
		g[i] = make([]int, n+1)
		ints := eGetInts(scanner)
		num := ints[0]
		for j := 0; j < ints[1]; j++ {
			g[num][ints[j+2]] = 1
		}
	}
	dist := make([]int, n+1)
	for i := 0; i < len(dist); i++ {
		dist[i] = -1
	}
	q := []int{}

	// 訪問する
	q = append(q, 1)
	dist[1] = 0

	// キューが空でない限り
	for len(q) > 0 {
		// 先頭を取り出す
		top := 0
		top, q = q[0], q[1:]
		// 隣接マスを入れる.
		for i := 1; i < n+1; i++ {
			// 辺がある
			if g[top][i] == 1 {
				if dist[i] == -1 {
					// 訪問済みでなければ
					q = append(q, i)
					dist[i] = dist[top] + 1
				}
			}
		}
	}
	for i := 1; i < n+1; i++ {
		fmt.Println(i, dist[i])
	}
}

////////////////////////////////////////////////////////////////////////////////
// ライブラリ
////////////////////////////////////////////////////////////////////////////////
func makeScanner(maxByte int) *bufio.Scanner {
	scanner := bufio.NewScanner(os.Stdin)
	scanner.Buffer(make([]uint8, 0, 8192), maxByte)
	return scanner
}
func makeWordScanner() *bufio.Scanner {
	scanner := makeScanner(8192)
	scanner.Split(bufio.ScanWords)
	return scanner
}
func eGetLine(r *bufio.Scanner) string {
	if r.Scan() {
		return r.Text()
	}
	err := r.Err()
	if err != nil {
		log.Fatal(err)
	}
	// EOF
	return ""
}
func eGetInt(r *bufio.Scanner) int {
	line := eGetLine(r)
	return eAtoi(line)
}
func eGetInt64(r *bufio.Scanner) int64 {
	line := eGetLine(r)
	return eAtoInt64(line)
}
func eGetFields(r *bufio.Scanner) []string {
	line := eGetLine(r)
	return strings.Fields(line)
}
func eGetInts(r *bufio.Scanner) []int {
	fields := eGetFields(r)
	ints := make([]int, len(fields))
	for i := 0; i < len(ints); i++ {
		ints[i] = eAtoi(fields[i])
	}
	return ints
}
func eGetInt64s(r *bufio.Scanner) []int64 {
	fields := eGetFields(r)
	ints := make([]int64, len(fields))
	for i := 0; i < len(ints); i++ {
		ints[i] = eAtoInt64(fields[i])
	}
	return ints
}
func eGetChars(r *bufio.Scanner) []string {
	line := eGetLine(r)
	return strings.Split(line, "")
}
func eAtoi(s string) int {
	n, err := strconv.Atoi(s)
	if err != nil {
		log.Fatal(err)
	}
	return n
}
func eAtoInt64(s string) int64 {
	n, err := strconv.ParseInt(s, 10, 64)
	if err != nil {
		log.Fatal(err)
	}
	return n
}

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

#define FOR(i, a, b) for(long long int i=(a);i<=(b);i++)
#define RFOR(i, a, b) for(long long int i=(a);i>=(b);i--)
#define MOD 1000000007
#define INF 1000000000 //2000000000
#define LLINF 1000000000000000000 //9000000000000000000
#define PI 3.14159265358979

using namespace std;
typedef long long int ll;
typedef pair< long long int, long long  int> P;

int n;
int u, k, v;
int hour = 0;
int pos;
int d[101];
int gra[101][101] = {};
int color[101] = {};
queue<int>que;



int main(void) {
	cin >> n;
	
	FOR(i, 1, n) {
		cin >> u >> k;
		FOR(t, 1, k) {
			cin >> v;
			gra[u][v] = 1;
		}
	}

	FOR(i, 1, n) {
		d[i] = -1;
	}

	que.push(1);
	d[1] = hour;
	color[1] = 1;
	
	while (que.empty() != 1) {
		pos = que.front();
		que.pop();
		FOR(i, 1, n) {
			if (gra[pos][i] == 1 && color[i] == 0) {
				que.push(i);
				d[i] = d[pos] + 1;
				color[i] = 1;
			}
		}
	}

	FOR(i, 1, n) {
		cout << i << " " << 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();
    q.pop();
    for (v = 0; v < n; v++) {
      if (M[u][v] == 0) continue;
      if (d[u] != INFTY) continue;
      q.push(v);
      d[v] = d[u] + 1;
    }
  }
  for (u = 0; u < n; u++) {
    cout << u + 1 << ' ' << ((d[u] == INFTY) ? (-1) : d[u]) << endl;
  }
}

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

  for (i = 0; i < n; i++) {
    d[i] = INFTY;
  }

  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++: #include <bits/stdc++.h>
using namespace std;
using pii=pair<int,int>;
using ll=long long;
using pll=pair<ll,ll>;

#define fi first
#define se second
#define pb push_back
#define rep(i,n) for(int i=0; i<(int)(n); i++)
#define MOD 1000000007

template<class T>bool chmax(T &a, const T &b) { if (a<b) { a=b; return 1; } return 0; }
template<class T>bool chmin(T &a, const T &b) { if (b<a) { a=b; return 1; } return 0; }
vector<vector<int> > G(110, vector<int>());

int main() {
	int N;
	cin >> N;
	int u,k;
	rep(i,N) {
		cin >> u >> k;
		u--;
		G[u] = vector<int>(k);
		rep(j,k) cin >> G[u][j], G[u][j]--;
	}

	queue<int> q;
	vector<int> dist(N, 1e9);
	dist[0] = 0;
	q.push(0);
	while(!q.empty()) {
		int p = q.front();
		q.pop();
		for(auto k : G[p]) {
			if(dist[k] > dist[p] + 1) {
				dist[k] = dist[p] + 1;
				q.push(k);
			}
		}
	}
	rep(i,N) if(dist[i] == 1e9) dist[i] = -1;
	rep(i,N) cout << i+1 << " " << dist[i] << endl;


  return 0;
}

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

using namespace std;

void bfs(vector<vector<int>> matrix) {
	
	//初期化
	//始点からの距離は1次元vectorで管理
	//始点から各頂点への距離をinf(-1)に設定
	int n = matrix.size();
	vector<int> d(n, -1);
	
	//始点をキューに入れる。始点の距離を0に
	queue<int> Q;
	Q.push(0);
	d.at(0) = 0;

	//以下ループ処理で距離の算出
	//キューが空になるまでこのループを回す
	while(! Q.empty()) {
		//キューの先頭の頂点を取り出す
		int head = Q.front();
		Q.pop();
		//その頂点から行ける点について-1なら
		for (int i = 0; i < matrix.at(0).size(); i++) {
			if (matrix[head][i] == 1 && d.at(i) == -1) {
				Q.push(i);
				d.at(i) = d.at(head) + 1;
			}
		}
	}

	// 表示
	for (int j = 0; j < d.size(); j++) {
		cout << j + 1 << " " << d.at(j) << endl;
	}
}

int main(void) {

	//標準入力を受け取る
	int n; //頂点数
	cin >> n;
	vector<vector<int>> matrix(n, vector<int>(n,0)); //隣接行列
	int u, k, v; //頂点番号、出次数、隣接する頂点番号
	for(int i = 0; i < n; i++) {
		cin >> u >> k;
		while(k--) {
			cin >> v;
			matrix.at(u-1).at(v-1) = 1; //有向グラフならこれだけ
			// matrix.at(v-1).at(u-1) = 1; //無向グラフなら反対向きも
		}
	}

	bfs(matrix);
	//
	// 隣接行列の表示
	// for(int i = 0; i < matrix.size(); i++) {
	//	 for(int j = 0 ;j < matrix.at(0).size(); j++) {
	//	 	cout << matrix.at(i).at(j) << " ";
	//	 }
	//	cout << endl;
	// }
}

//隣接リストどうやるの？

C++: #include <iostream>
#include <stdio.h>
#include <queue>
#define N 101
#define INFTY (1<<21)


int n;
int M[N][N];
int d[N];

void bfs(int u) {
    std::queue<int> Q;
    Q.push(u);
    for (int i = 0; i < n; i++) d[i] = INFTY;
    d[u] = 0;
    while ( ! Q.empty() ) {
        int j = Q.front();
        Q.pop();
        for (int v = 0; v < n; v++) {
            if (M[j][v] == 0) continue;
            if (d[v] != INFTY) continue;
            d[v] = d[u] + 1;
            Q.push(v);
        }
    }
    for (int i = 0; i < n; i++) {
        printf("%d %d\n", i+1, d[i]);
    }
}

int main() {
    int u, k, v;
    scanf("%d", &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++) {
        scanf("%d %d", &u, &k);
        u--;
        if (k == 0) continue;
        for (int j = 0; j < k; j++) {
            scanf("%d", &v);
            v--;
            M[u][v] = 1;
        }
    }
    
    bfs(0);
    
    return 0;
}