Go: package main

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

func main() {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)
	sc.Scan()
	num, _ := strconv.Atoi(sc.Text())
	nodes := make(map[int]*node)

	for i := 0; i < num; i++ {
		sc.Scan()
		id, _ := strconv.Atoi(sc.Text())
		sc.Scan()
		nodeNum, _ := strconv.Atoi(sc.Text())
		n := node{id, make([]int, 0), -1}
		for j := 0; j < nodeNum; j++ {
			sc.Scan()
			nid, _ := strconv.Atoi(sc.Text())
			n.nexts = append(n.nexts, nid)
		}
		nodes[id] = &n
	}
	nodes[1].depth = 0

	walk(1, 0, &nodes)
	for i := 1; i < len(nodes)+1; i++ {
		fmt.Printf("%v %v\n", (*nodes[i]).id, (*nodes[i]).depth)
	}
}

var time int
var record [100][100]bool
var q Queue

func walk(nid int, from int, nodes *map[int]*node) {
	q.Enqueue((*nodes)[nid])
	for !q.IsEmpty() {
		n := q.Dequeue().(*node)
		for _, v := range n.nexts {
			n2 := (*nodes)[v]
			if n2.depth != -1 {
				continue
			}
			n2.depth = n.depth + 1
			q.Enqueue((*nodes)[v])
		}
	}
}

type node struct {
	id    int
	nexts []int
	depth int
}

// Queue is Queue
type Queue struct {
	val []interface{}
}

// Enqueue value
func (queue *Queue) Enqueue(val interface{}) {
	queue.val = append(queue.val, val)
}

// Dequeue value
func (queue *Queue) Dequeue() interface{} {
	res := queue.val[0]
	queue.val = queue.val[1:len(queue.val)]
	return res
}

// IsEmpty return true when queue is empty
func (queue *Queue) IsEmpty() bool {
	return len(queue.val) == 0
}

Python: from sys import stdin
from collections import deque
n = int(input())
d = [-1] * (n + 1)
def bfs():
    d[1] = 0
    dq = deque([1])
    while len(dq) != 0:
        v = dq.popleft()
        for c in G[v]:
            if d[c] != -1 : continue
            d[c] = d[v] + 1
            dq.append(c)
    for i, x in enumerate(d[1:], start=1):
        print(i, x)
G = [0] + [list(map(int, input().split()[2:])) for i in range(n)]
bfs()

Python: from collections import deque
n = int(input())

g = [[] for _ in range(n)]
for i in range(n):
    _, _, *edge = map(lambda x: int(x)-1, input().split())

    g[i] = edge

q = deque()
q.append(0)
dist = [-1 for _ in range(n)]
dist[0] = 0

while(len(q) > 0):
    v = q.popleft()

    for nv in g[v]:
        if(dist[nv] != -1): continue
        
        dist[nv] = dist[v] + 1
        q.append(nv)

for i in range(n):
    print(i+1, dist[i])

Python: # -*- coding: utf-8 -*-                                                                                                                                                                                                                               

def BFS(adj, start):
    n = len(adj)
    d = [-1] * n
    flag = [0] * n
    Q = []

    Q.append(start)
    d[start] = 0
    flag[start] = 1

    while len(Q) != 0:
        u = Q.pop(0)
        v = [i for i, x in enumerate(adj[u]) if (x == 1) and (flag[i] == 0)] # v <= ??£??\???????????????????????¢?´¢??????????????????
        
        for i in v:
            Q.append(i)
            d[i] = d[u] + 1
            flag[i] = 1
    
    return d

def main():
    n = int(input())
    adj = [[0 for i in range(n)] for j in range(n)]
    
    for i in range(n):
        tmp = list(map(int, input().split()))
        u = tmp[0]
        u = u -1
        k = tmp[1]
        v = tmp[2:]
        for j in range(k):
            adj[u][v[j]-1] = 1
    
    d = BFS(adj, 0)
    for i in range(n):
        print(i+1, d[i])


if __name__ == "__main__":
    main()

Python: from collections import deque
N = int(input())
g = {i: deque() for i in range(1,N+1)} #1-index
for i in range(1, N+1):
    u, k, *v = map(int, input().split())
    for j in v:
        g[u].append(j)
        
seen = [0]*(N+1) #1-index
que = deque([])
dist = [-1]*(N+1) #1-index

seen[1] = 1
que.append(1)
dist[1] = 0

while que: #queが空になるまで
    q_no = que.popleft()
    if not g[q_no]: continue #点q-noから他の点に伸びていない
    
    for next_v in g[q_no]:
        if seen[next_v] == 1: continue #訪問済
        
        seen[next_v] = 1 #訪問済にする
        dist[next_v] = dist[q_no] + 1 #距離情報を格納
        que.append(next_v) #queに追加

for i in range(1, N+1):
    print(i, dist[i])

Python: from collections import deque
n=int(input())
l=[0]+[list(map(int,input().split()))[2:] for _ in range(n)]

flg=["white"]*(n+1)
dist=[-1]*(n+1)

def BFS(x):

    queue = deque([x])
    dist[x]=0
    flg[x]="gray"

    while queue:
        current=queue.popleft()
        for i in l[current]:
            if flg[i]=="white":
                queue.append(i)
                flg[i]="gray"
                dist[i]=dist[current]+1
        flg[current]="black"

BFS(1)

for num,i in enumerate(dist[1:],1):
    print(num,i)

Python: import queue
N=int(input())
M=[input().split()[2:]for _ in[0]*N]
q=queue.Queue();q.put(0)
d=[-1]*N;d[0]=0
while not q.empty():
 u=q.get()
 for v in M[u]:
  v=int(v)-1
  if d[v]<0:d[v]=d[u]+1;q.put(v)
for i in range(N):print(i+1,d[i])

Python: cin = open(0).read().strip().split('\n')
n = int(cin[0])
v = [list(map(lambda x: int(x)-1, a.split(' ')[2:])) for a in cin[1:]]

import queue
q = queue.Queue()
q.put(0)

dist = [-1]*n
dist[0] = 0
seen = [False]*n
while not q.empty():
    num = q.get()
    seen[num] = True
    for a in v[num]:
        if dist[a] != -1: continue
        dist[a] = dist[num] + 1
        q.put(a)

for idx, num in enumerate(dist):
    print(idx+1, num)

Python: import sys
import queue
readline = sys.stdin.readline
write = sys.stdout.write

n = int(input())
G = [None for i in range(n+1)]
dist = [-1,]*(n+1)
for i in range(n):
    node_id, k, *adj = map(int, readline().split())
    # adj.sort()
    G[node_id] = adj

def bfs(G):
    #q1が空でなければcntをインクリメントして下のブロックの処理を行う
        #q1から要素取り出し
        #→既に見た節点ならばそれに対しては処理を行わずq1から要素を取り出す(節点1⇔節点2の時の無限ループ回避)
        #→最短距離を格納した後,その要素の子をq2に入れる
        #→q1から要素が無くなったらq2の要素を全てq1に入れる
    cnt = -1

    q1 = queue.Queue()
    q2 = queue.Queue()
    q1.put(1)
    while not q1.empty():
        cnt += 1
        while not q1.empty():
            val = q1.get()
            if dist[val] != -1:
                continue
            dist[val] = cnt
            listlen = len(G[val])
            for i in range(listlen):
                q2.put(G[val][i])
        while not q2.empty():
            q1.put(q2.get())
bfs(G)
for i in range(1, n+1):
    write(str(i) + " " + str(dist[i]) + "\n")

Python: import queue
N=int(input())
M=[input().split()[2:]for _ in[0]*N]
q=queue.Queue();q.put(0)
d=[-1]*N;d[0]=0
while q.qsize()>0:
 u=q.get()
 for v in M[u]:
  v=int(v)-1
  if d[v]<0:d[v]=d[u]+1;q.put(v)
for i in range(N):print(i+1,d[i])

Python: def BFS(s, r):
    d[s] = r
    for i in range(1, n+1):
        if G[s][i] == 1 and flag[i] == 0:
            BFS(i, r+1)

n = int(raw_input())
G = [[0 for i in range(n+1)] for j in range(n+1)]
d = [-1 for i in range(n+1)]

for i in range(n):
    v = map(int, raw_input().split())
    for j in range(v[1]):
        G[v[0]][v[2+j]] = 1

flag = [0 for i in range(n+1)]
BFS(1, 0)

for i in range(1, n+1):
    print(str(i) + " " + str(d[i]))

Python: n = int(raw_input())

G = [0 for i in range(n)] 
a = [[0 for i in range(n)] for j in range(n)]
dis = [-1 for i in range(n)]

for i in range(n):
    G = map(int, raw_input().split())
    for j in range(G[1]):
        a[G[0]-1][G[2+j]-1] = 1

def bfs_visit(s):
    for k in range(n):
      if a[s][k] == 1 and dis[k] == -1:
         dis[k] = dis[s] + 1
         bfs_visit(k)

for s in range(s):
    bfs_visit()
for s in range(s):
    print (s+1,dis[s])