Go: package main

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

//util
var sc = bufio.NewScanner(os.Stdin)

func nextStr() string {
	sc.Scan()
	return sc.Text()
}

func nextInt() int {
	sc.Scan()
	i, e := strconv.Atoi(sc.Text())
	if e != nil {
		panic(e)
	}
	return i
}

func printList(list []int) {
	n := len(list)
	buf := bufio.NewWriter(os.Stdout)
	for _, v := range list[0 : n-1] {
		buf.Write([]byte(fmt.Sprintf("%d ", v)))
	}
	buf.Write([]byte(fmt.Sprintf("%d\n", list[n-1])))
	buf.Flush()
}

func max(a, b int) int {
	if a > b {
		return a
	} else {
		return b
	}
}

func min(a, b int) int {
	if a > b {
		return b
	} else {
		return a
	}
}

//solve
const INFTY = (1 << 21)
const MAX = 100
const WHITE = 0
const GRAY = 1
const BLACK = 2

var time, n int

//隣接行列
var M [MAX][MAX]int

//d[i]: 頂点1から頂点iまでの距離
var color, d [MAX]int

func bfs(s int) {
	var q []int
	q = append(q, s)
	for i := 0; i < n; i++ {
		d[i] = INFTY
	}
	//sは開始点なので、0をいれる
	d[s] = 0

	//キューが空になるまで、以下を繰り返す
	for len(q) > 0 {
		u := q[0]
		q = q[1:]
		for v := 0; v < n; v++ {
			if M[u][v] == 0 {
				continue
			}
			if d[v] != INFTY {
				continue
			}
			d[v] = d[u] + 1
			q = append(q, v)
		}
	}

	for i := 0; i < n; i++ {
		fmt.Printf("%d ", i+1)
		if d[i] == INFTY {
			fmt.Printf("%d\n", -1)
		} else {
			fmt.Printf("%d\n", d[i])
		}
	}
}

func main() {
	sc.Split(bufio.ScanWords)
	n = nextInt()
	for i := 0; i < n; i++ {
		u, k := nextInt(), nextInt()
		M[u-1][u-1] = 0

		//fmt.Println(u, k)
		if k > 0 {
			for j := 0; j < k; j++ {

				v := nextInt()
				M[u-1][v-1] = 1

			}
		}

	}

	bfs(0)

}

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

#include <cassert>
#include <climits>

#include <string.h>

#include <vector>
#include <map>
#include <stack>
#include <deque>

enum Color
{
    kWhite,
    kGray,
    kBlack,
};

int n;
int start_vertex = 0;
std::vector< std::vector<int> > matrix;
std::vector<Color> c;
std::vector<int> d;

void breadthFirstSearch()
{
    for (int i = 0; i < n;++i)
    {
        c.push_back(kWhite);
        d.push_back(-1);
    }

    std::deque<int> tmp_queue;
    tmp_queue.push_back(start_vertex);
    c[start_vertex] = kGray;
    d[start_vertex] = 0;

    while (! tmp_queue.empty())
    {
        int current = tmp_queue.front();
        tmp_queue.pop_front();
        c[start_vertex] = kBlack;

        std::vector<int> line = matrix[current];
        for (int i = 0; i < line.size(); ++i)
        {
            if (line[i] > 0 && c[i] == kWhite)
            {
                tmp_queue.push_back(i);
                c[i] = kGray;
                d[i] = d[current] + 1;
            }
        }
    }
}

int main()
{
    std::cin >> n;
    for (int i = 0; i < n; ++i)
    {
        std::vector<int> line;
        for (int j = 0; j < n; ++j)
        {
            line.push_back(0);
        }
        matrix.push_back(line);
    }

    for (int i = 0; i < n; ++i)
    {
        int u;
        int k;

        std::cin >> u;
        std::cin >> k;

        for (int j = 0; j < k; ++j)
        {
            int tmp;
            std::cin >> tmp;
            matrix[u - 1][tmp - 1] = 1;
        }
    }

    breadthFirstSearch();

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

    return 0;
}

C++: #include <iostream>
#include <vector>
#include <queue>
using namespace std;

vector<int> bfs(vector<vector<int>> &adj_list)
{
    vector<int> res(adj_list.size(), -1);
    vector<bool> visit(adj_list.size(), 0);
    queue<int> q;
    q.push(0);
    visit[0] = 1;
    res[0] = 0;

    while (!q.empty())
    {
        int u = q.front();
        q.pop();
        for (int i = 0; i < adj_list[u].size(); i++)
        {
            int v = adj_list[u][i];
            if (visit[v] == 0)
            {
                visit[v] = 1;
                res[v] = res[u] + 1;
                q.push(v);
            }
        }
    }

    return res;
}

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

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

    // for (int i = 0; i < n; i++)
    // {
    //     for (int j = 0; j < adj_list[i].size(); j++)
    //     {
    //         cout << adj_list[i][j] << ", ";
    //     }
    //     cout << endl;
    // }

    vector<int> res = bfs(adj_list);
    for (int i = 0; i < n; i++)
    {
        cout << i + 1 << " " << res[i] << endl;
    }

    return 0;
}

C++: /*
?????????: Graph I - Breadth First Search
URL: http://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=ALDS1_11_C
?????°
19:08 ??°?????????????????????????????£??¨??????????????????????????§???????????????????????£?????????
19:08 ???????????\????????\????????°??????????????????????¢????
19:09 ????????°???????????????????§£
19:13 ??¨???????????????????????£???
19:19 BFS????¨???¶???????¶??????????????????§??¨?????????????????????????????????
19:28 ???????????????????§?????????????????????£????????§????????????????????????????????????????????§????????????????????£????????????
19:29 ?????????????????????????????????????????? 1 ????????????????????????????????????????????????????????¢??¨??????-1 ?????????????????????????????????
*/
#include <iostream>
#include <vector>
#include <set>
#include <queue>
#define INF 114514
using namespace std;

int main()
{
	int n; cin>>n;
	vector< set<int> > graphdat(n+1);  
	for(int i=0;i<n;i++){
		int u; int k; cin >> u >> k;
		set<int> v;
		for(int j=0;j<k;j++){
			int tmp;
			cin >> tmp;
			v.insert(tmp);
		}
		graphdat[u] = v;
	}

	vector<int> distance(n+1);
	distance[1] = 0;
	for(int i=2;i<=n;i++){
		distance[i] = INF;
	}

	queue<int> Q;
	Q.push(1);

	while(!Q.empty()) {
		int cur = Q.front();
		Q.pop(); // pop?????????????????????????????¨?¬???\??§??????
		for(int dest=1; dest<=n; dest++) {
			if(graphdat[cur].find(dest) != graphdat[cur].end()) { // ??????????????????
				if(distance[dest] > distance[cur] + 1) { // ??´??°??§????????????
					distance[dest] = distance[cur] + 1;
					Q.push(dest);
				}
			}
		}
	}

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

}

C++: #include <cstdio>
#include <iostream>
#include <queue>
using namespace std;

static const int MAX_NUM = 101;
static const int NO_VISIT  = 0;
//static const int NOW_VISIT = 1;
static const int END_VISIT = 2;

void BFS(int *matrix, int num)
{
    int i;
    int state[MAX_NUM]    = {0};
    int distance[MAX_NUM];
    queue<int> Q;
    int target;
    int dist = 0;
    int *tmp;
    bool first;

    for (i = 1; i <= num; i++) {
        distance[i] = -1;
    }

    Q.push(1);
    state[1] = END_VISIT;
    distance[1] = 0;

    while (Q.empty() == false) {
        target = Q.front();
        Q.pop();
        tmp = matrix + target * MAX_NUM;
        first = true;
        for (i = 1; i <= num; i++) {
            if ((*(tmp + i) == 1) && (state[i] == NO_VISIT)) {
                distance[i] = distance[target] + 1;
                Q.push(i);
                state[i] = END_VISIT;
            }
        }
    }

    for (i = 1; i <= num; i++) {
        printf("%d %d\n", i, distance[i]);
    }

    return;
}

int main(void)
{
    int i, j;
    int num;
    int elem;
    int nume;
    int tmp;
    int matrix[MAX_NUM][MAX_NUM];

    scanf("%d", &num);
    for (i = 0; i < num; i++) {
        scanf("%d %d", &elem, &nume);
        for (j = 0; j < nume; j++) {
            scanf("%d", &tmp);
            matrix[elem][tmp] = 1;
        }
    }

    BFS(&matrix[0][0], num);

    return 0;
}