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<iostream>
#include<cstdio>
#include<cstring>
#include<queue>
using namespace std;
const int MAX=105;
int M[MAX][MAX];
int dis[MAX],n;
bool inq[MAX];
void bfs(int cur){
	queue<int> Q;
	Q.push(cur);
	dis[cur]=0;
	while(!Q.empty()){
		int u=Q.front();
		Q.pop();
		for(int i=1;i<=n;i++){
			if(M[u][i]&&!inq[i]){
				if(dis[i]==-1)dis[i]=dis[u]+1;
				else dis[i]=min(dis[i],dis[u]+1);
				Q.push(i);
				inq[i]=1;
			}
		}
	}
}
int main(){
	int u,k;
	cin>>n;
	memset(M,0,sizeof(M));
	memset(dis,-1,sizeof(dis));
	memset(inq,0,sizeof(inq));
	for(int i=0;i<n;i++){
		cin>>u>>k;
		int v;
		for(int j=0;j<k;j++){
			cin>>v;
			M[u][v]=1;
		}
	}
	bfs(1);	
	for(int i=1;i<=n;i++){
		printf("%d %d\n",i,dis[i]);
	}
	return 0;
}

C++: #include <iostream>
#include <algorithm>
#include <queue>
#define N 100
using namespace std;

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


void bfs(int s) {
	queue<int> Q;
	for (int i = 0;i < n;i++) d[i] = -1;
	d[s] = 0;
	Q.push(s);
	color[s] = 1;
	while (!Q.empty()) {
	  for (int i = 0;i < n;i++)
		  if (M[Q.front()][i] == 1) {
			  if (color[i] == 0) {
				  d[i] = d[Q.front()] + 1;
				  color[i] = 1;
				  Q.push(i);
			  }
		  }
		  Q.pop();
	}
	for (int i = 0;i < n;i++)
		cout << i + 1 << " " << d[i] << endl;
}


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

	bfs(0);

}

C++: #include <iostream>
#include <string>
#include <vector>
#include <set>
#include <cstdio>
#include <cstdlib>
#include <algorithm>
#include <functional>
#include <map>
#include <cmath>
#include <queue>

using namespace std;

static const int N = 100;

int main() {

    int graph[N][N] = {0};
    int distance[N] = {-200000};
    bool alreadySearched[N] = {false};

    int n;scanf("%d",&n);
    for(int i=0;i<n;i++){
        int u;scanf("%d",&u);
        u--;
        int k;scanf("%d",&k);
        for(int j=0;j<k;j++){
            int v;scanf("%d",&v);
            v--;
            graph[u][v] = 1;
        }
    }


    queue<int> Q;
    Q.push(0);
    distance[0] = 0;
    alreadySearched[0] = true;

    while(!Q.empty()){
        int u = Q.front();
        for(int i=0;i<n;i++){
            if(!alreadySearched[i] && graph[u][i] == 1){
                Q.push(i);
                alreadySearched[i] = true;
                distance[i] = distance[u] + 1;
            }
        }
        Q.pop();
    }

    for(int i=0;i<n;i++){
        if(!alreadySearched[i]){
            distance[i] = -1;
        }
    }
    for(int i=0;i<n;i++){
        printf("%d %d\n", i+1, distance[i]);
    }

    return 0;
}

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];  // 距離で訪問状態(color)を管理する

void bfs(int s)
{
    queue<int> q;  // 標準ライブラリのqueueを使用
    q.push(s);
    for (int i = 0; i < n; i++) {
        d[i] = INFTY;  // 距離を十分に大きい値に初期化する
    }
    d[s] = 0;  // s(始点)の距離を0とする
    int u;
    while(!q.empty()) {  // キューにキーがある限り実行
        u = q.front();  // キューの一番上の要素をuにして
        q.pop();  // 削除
        for (int v = 0; v < n; v++) {
            if (M[u][v] == 0) {  // uからvへのパスがなければ次へ
                continue;
            }
            if (d[v] != INFTY) {  // 距離が十分に大きくなければ次へ
                continue;
            }
            d[v] = d[u] + 1;  // d[v]にd[u]の距離+1を入れる
            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++: #include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define REP(i,n) for(ll i=0; i<(n); i++)
#define REP2(i,x,n) for(ll i=x; i<(n); i++)
#define REP3(i,x,n) for(ll i=x; i>(n); i--)
#define ALL(n) begin(n),end(n)
#define MAX 500000
#define SENTINEL 2000000000
#define NIL -1
static const int N=100;
static const int INFTY = (1<<21);
struct cww{cww(){ios::sync_with_stdio(false);cin.tie(0);}}star;
const long long INF = numeric_limits<long long>::max();
int n,M[N][N];
int d[N];//訪問状態の管理


void bfs(int s){
    queue<ll>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;
}