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<cstdio>
#include<queue>
#include<iostream>
using namespace std;
int n, visited[101], d[101];
int adj[101][101];
queue<int> q;
void bfs(int u)
{
  if(visited[u]) return;
  q.push(u);
  visited[u] = 1;
  while(!q.empty())
  {
    int v = q.front();
    for(int i=1; i<=n; i++)
    {
      if(adj[v][i] && visited[i]==0)
      {
        q.push(i);
        visited[i] = 1;
        d[i] = d[v] + 1;
      }
    }
    q.pop();
  }
}
int main()
{
  scanf("%d", &n);
  for(int i=0; i<=n; i++)
  {
    for(int j=0; j<=n; j++)
      adj[i][j] = 0;
    visited[i] = 0;
    d[i] = -1;
  }
  d[1] = 0;
  int u, k, v;
  for(int i=0; i<n; i++)
  {
    scanf("%d%d", &u, &k);
    for(int j=0; j<k; j++)
    {
      scanf("%d", &v);
      adj[u][v] = 1;
    }
  }
//  for(int i=1; i<=n; i++)
//  {
//    if(visited[i] == 0)
//      bfs(i);
//  }
  bfs(1);
  for(int i=1; i<=n; i++)
  {
    printf("%d %d\n", i, d[i]);
  }


  return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef pair<ll, ll> P;

#define pb push_back
#define rep(i, n) for(int i = 0; i < (n); i++)
#define FOR(i, a, n) for(int i = a; i < (n); i++)
#define mod (ll)(1e9+7)
#define int ll

static const int N = 100;
static const int no = -1;

__attribute__((constructor))
void initial() {
  cin.tie(0);
  ios::sync_with_stdio(false);
}

ll graph[N][N] = {0}, d[N] = {0}, n;

void bfs(int v) {
  queue<int> q;
  q.push(v);
  ll u;
  for(int i = 1; i <= n; i++) d[i] = no;
  d[v] = 0;
  while(!q.empty()) {
    u = q.front(); q.pop();
    for(int i = 1; i <= n; i++) {
      if((graph[u][i] == 0) || (d[i] != no)) continue;
      d[i] = d[u] + 1;
      q.push(i);
    }
  }
}

signed main() {
	ll u, v, k;
  cin >> n;
  rep(i, n) {
    cin >> u >> k;
    rep(j, k) {
      cin >> v;
      graph[u][v] = 1;
    }
  }

  bfs(1);

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

	return 0;
}

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

int A[101][101] = {0};
int n, tt = 0, d[101] = {0}, color[101] = {0};
queue<int> Q;


void bfs (int u) {
    int i, j ,k;
    Q.push(u);
    d[u] = tt++;
    color[u] = 1;
    while ( !Q.empty() ) {
        j = Q.front();
        Q.pop();
        for ( i = 1; i <= n; i++ ) {
            if ( A[j][i] == 1 && color[i] != 1 ) {
                Q.push(i);
                color[i] = 1;
                d[i] = d[j] + 1;
            }

        }
        }
    }



int main() {
    int i, j, k, v;
    cin >> n;
    for ( i = 0; i < n; i++ ) {
        cin >> j >> k;
        while ( k-- ) {
            cin >> v;
            A[j][v] = 1;
        }
    }

    bfs(1);
    for ( i = 1; i <= n; i++ ) if ( color[i] != 1 ) d[i] = -1;
    for ( i = 1; i <= n; i++ ) cout << i << ' ' << d[i] << endl;

    return 0;

}

C++: #include<iostream>
#include<queue>
using namespace std;
int N;
int D[101];
void bfs(int src){
    int u[101],k[101],a[10010],d[101][101];
    bool visit[101];
    for(int i=1;i<=N;++i){
        cin>>u[i]>>k[i];
        for(int j=0;j<k[i];++j){
            cin>>a[j];
            d[u[i]][a[j]]=1;
        }
        visit[i]=true;
    }
    queue<int>Q;
    Q.push(src);
    D[src]=0;
    visit[src]=false;
    while(!Q.empty()){
        int cur=Q.front();
        Q.pop();
        for(int i=1;i<=N;++i){
            if(d[cur][i]==1&&visit[i]){
                visit[cur]=false;
                visit[i]=false;
                D[i]=D[cur]+1;
                Q.push(i);
            }
        }
    }
    for(int i=1;i<=N;++i){
        if(i!=1&&D[i]==0){
            D[i]=-1;
        }
        cout<<i<<" "<<D[i]<<endl;
    }
}
int main(){
    cin>>N;
    int start=1;
    bfs(start);
}

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

int M[101][101], cond[101], d[101], n;

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

void bfs(int x)
{
	queue<int> Q;

	Q.push(x);
	cond[x] = -1;
	d[x] = 0;

	while (!Q.empty()) {
		int u = Q.front();
		for (int i = 1; i <= n; i++) {
			if (M[u][i] == 1 && cond[i] == 0) {
				Q.push(i);
				d[i] = d[u] + 1;				
				cond[i] = -1;
			}
		}
		Q.pop();
		cond[u] = 1;
	}
}

int main()
{
	ios::sync_with_stdio(false);
	cin.tie(0);

	cin >> n;
	setAdj();

	for (int i = 1; i <= n; i++)
		if (cond[i] == 0) bfs(i);

	for (int i = 1; i <= n; i++)
		cout << i << " " << d[i] << endl;

	return 0;
}