Go: package main

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

var scanner = bufio.NewScanner(os.Stdin)

func nextString() string {
	scanner.Scan()
	return scanner.Text()
}

func nextInt() int {
	n, err := strconv.Atoi(nextString())
	if err != nil {
		fmt.Printf("strconv.Atoi failed: %v\n", err)
	}
	return n
}

func stringifyArray(arr []int) string {
	return strings.TrimRight(fmt.Sprintf("%+v", arr)[1:], "]")
}

var infty = 1000000000

type nodeKey int

type DirectedGraphNode struct {
	key       nodeKey
	adjacents []*DirectedGraphNode
	visited   bool
	d         int
	parent    *DirectedGraphNode
}

type DirectedGraph struct {
	nodes []DirectedGraphNode
}

func (g *DirectedGraph) setAdjacency(l, r nodeKey) {
	g.nodes[l].adjacents = append(g.nodes[l].adjacents, &g.nodes[r])
}

func newDirectedGraph(nNodes int) *DirectedGraph {
	graph := DirectedGraph{}
	graph.nodes = make([]DirectedGraphNode, nNodes)
	for iNodes := 0; iNodes < nNodes; iNodes++ {
		graph.nodes[iNodes].key = nodeKey(iNodes)

		graph.nodes[iNodes].visited = false
		graph.nodes[iNodes].d = infty
		graph.nodes[iNodes].parent = nil
	}
	return &graph
}

type QueueEntry struct {
	node *DirectedGraphNode
	next *QueueEntry
}

type Queue struct {
	head, tail *QueueEntry
}

func (q *Queue) enqueue(node *DirectedGraphNode) {
	entry := QueueEntry{}
	entry.node = node

	if q.tail == nil {
		q.head = &entry
		q.tail = &entry
		return
	}

	q.tail.next = &entry
	q.tail = q.tail.next
}

func (q *Queue) dequeue() *QueueEntry {
	if q.head == nil {
		return nil
	}
	poped := q.head
	q.head = q.head.next
	if q.head == nil {
		q.tail = nil
	}
	return poped
}

func (q *Queue) isEmpty() bool {
	return q.head == nil
}

func fillDistancesByBreadthFirstSearch(g *DirectedGraph, startNode *DirectedGraphNode) {
	startNode.visited = true
	startNode.d = 0

	queue := Queue{}
	queue.enqueue(startNode)
	for !queue.isEmpty() {
		u := queue.dequeue().node
		for _, adjacent := range u.adjacents {
			if !adjacent.visited {
				adjacent.visited = true
				adjacent.d = u.d + 1
				adjacent.parent = u
				queue.enqueue(adjacent)
			}
		}
		u.visited = true
	}
}

func main() {
	scanner.Split(bufio.ScanWords)

	nNodes := nextInt()
	g := newDirectedGraph(nNodes + 1)

	for iNode := 0; iNode < nNodes; iNode++ {
		nodeKeyLeft := nodeKey(nextInt())
		nAdj := nextInt()
		for iAdj := 0; iAdj < nAdj; iAdj++ {
			nodeKeyRight := nodeKey(nextInt())
			g.setAdjacency(nodeKeyLeft, nodeKeyRight)
		}
	}

	// fmt.Println(g)
	fillDistancesByBreadthFirstSearch(g, &g.nodes[1])
	// fmt.Println(g)

	for iNode := 1; iNode <= nNodes; iNode++ {
		node := g.nodes[iNode]
		distance := node.d
		if distance == infty {
			distance = -1
		}
		fmt.Println(node.key, distance)
	}
}

C++: #include <bits/stdc++.h>
#define rep(i, n) for(int i = 0; i < (n); ++i)
using namespace std;


int G[100][100];
int d[100]={0};
queue<int> que;
int distance_from0 = 1;

int main() {
    // 制約見て！！！デカかったらlong longにすること！
    int n, u, k, v;
    cin >> n;
    rep(i, n) {
        cin >> u >> k;
        u--;
        rep(j, k) {
            cin >> v;
            v--;
            G[u][v] = 1;
        }
    }
    que.push(0);
    d[0]=0;
    while(que.size()>0){
        int s = que.front();
        que.pop();
        rep(i,n){
            if(i>0 && d[i]==0 && G[s][i]==1){
                que.push(i);
                d[i] = d[s]+1;
            }
        }
    }

    rep(i,n){
        if(i>0 && d[i]==0){
            d[i] = -1;
        }
    }
    rep(i,n){
        printf("%d %d\n",i+1,d[i]);
    }
}

C++: #define _CRT_SECURE_NO_WARNINGS
#include <cstdio>
#include <cstdlib>
#include <string>
#include <iostream>
#include <climits>
#include <stack>
#include <queue>

using namespace std;

int main() {
	queue<int> Q;
	int n;
	int u, v;
	int AdjList[101][99];
	int Deg[101];
	bool Visited[101];
	int d[101];
	int i, j;
	cin >> n;
	for (i = 1; i <= n; i++) {
		d[i] = -1;
		Visited[i] = false;
		cin >> u;
		cin >> Deg[u];
		for (j = 0; j < Deg[u]; j++) {
			cin >> v;
			AdjList[u][j] = v;
		}
	}

	d[1] = 0;
	Q.push(1);
	Visited[1] = true;
	while (Q.empty() != true) {
		v = Q.front();
		Q.pop();
		for (i = 0; i < Deg[v]; i++) {
			u = AdjList[v][i];
			
			if (Visited[u] != true) {
				Visited[u] = true;
				d[u] = d[v] + 1;
				Q.push(u);
			}
		}
	}
	for (i = 1; i <= n; i++) {
		printf("%d %d\n", i, d[i]);
	}

	return 0;
}

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

using namespace std;

static const int N = 100;
static const int NEW = 0;
static const int VISITING = 1;
static const int OLD = 2;

int n, m[N][N] = {0}, t;
int color[N] = { 0 }, t1[N] = { 0 }, t2[N] = {0};

void getMatrix()
{
	int u, v, k;
	cin >> n;
	for (int i = 0; i < n; ++i)
	{
		cin >> u >> k;
		for (int j = 0; j < k; ++j)
		{
			cin >> v;
			m[u-1][v-1] = 1;
		}
	}
}

int nxt(int idx)
{
	for (int i = 0; i < n; ++i)
	{
		if (1 == m[idx][i] && color[i] == NEW)
			return i;
	}
	return -1;
}

void dfs_visit(int idx)
{
	stack<int> s;
	s.push(idx);
	color[idx] = VISITING;
	t1[idx] = t++;


	while (!s.empty())
	{
		int u = s.top();
		int v = nxt(u);
		if (-1 != v)
		{
			color[v] = VISITING;
			t1[v] = t++;
			s.push(v);
		}
		else
		{
			s.pop();
			color[u] = OLD;
			t2[u] = t++;
		}
	}
}

void dfs()
{
	t = 1;

	for (int i = 0; i < n; ++i)
		color[i] = NEW;

	for (int i = 0; i < n; ++i)
	{
		if (color[i] == NEW)
			dfs_visit(i);
	}

	for (int i = 0; i < n; ++i)
	{
		cout << i + 1 << " " << t1[i] << " " << t2[i] << endl;
	}
}

int dist[N];

void bfs(int idx)
{
	queue<int> q;
	q.push(idx);

	for (int i = 0; i < n; ++i)
		dist[i] = INT_MAX;
	dist[idx] = 0;

	int u;
	while (!q.empty())
	{
		u = q.front(); q.pop();
		for (int i = 0; i < n; ++i)
		{
			if (m[u][i] == 0) continue;
			if (dist[i] != INT_MAX) continue;
			dist[i] = dist[u] + 1;
			q.push(i);
		}
	}
	for (int i = 0; i < n; ++i)
	{
		cout << i + 1 << " " <<( (dist[i] == INT_MAX) ? (-1) : dist[i]) << endl;
	}
}


int main()
{
	getMatrix();
	bfs(0);
}