Go: package main

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

type vertexId int

type vertex struct {
	id vertexId
	visitedAt int
	adjs []vertexId
}

func createVertex(id int, adjsInt []int) vertex {
	adjs := make([]vertexId, len(adjsInt))
	for i := 0; i < len(adjs); i++ {
		adjs[i] = vertexId(adjsInt[i])
	}
	return vertex{
		id: vertexId(id),
		visitedAt: -1,
		adjs: adjs,
	}
}

func (v *vertex) isVisited() bool {
	return v.visitedAt >= 0
}

func bfs(id vertexId, vqueue []vertexId, vertices []vertex) {
	vertex := &vertices[id-1]
	for _, vid := range vertex.adjs {
		if !vertices[vid-1].isVisited() {
			(&vertices[vid-1]).visitedAt = vertex.visitedAt+1
			vqueue = append(vqueue, vid)
		}
	}
	if len(vqueue) > 0 {
		nextId := vqueue[0]
		nextVqueue := vqueue[1:]
		bfs(nextId, nextVqueue, vertices)
	}
}

func solveBfs(vertices []vertex) {
	vertex := &vertices[0]
	vertex.visitedAt = 0
	vqueue := make([]vertexId, 0)
	bfs(vertex.id, vqueue, vertices)
}

func main() {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)

	n, err := nextInt(sc)
	if err != nil {
		panic(err)
	}

	vertices := make([]vertex, n)
	for i := 0; i < n; i++ {
		id, err := nextInt(sc)
		if err != nil {
			panic(err)
		}
		adjN, err := nextInt(sc)
		if err != nil {
			panic(err)
		}
		adjs := make([]int, adjN)
		for j := 0; j < adjN; j++ {
			adjId, err := nextInt(sc)
			if err != nil {
				panic(err)
			}
			adjs[j] = adjId
		}
		vertices[i] = createVertex(id, adjs)
	}

	solveBfs(vertices)

	for i := 0; i < n; i++ {
		fmt.Printf("%d %d\n", vertices[i].id, vertices[i].visitedAt)
	}
}

func nextText(sc *bufio.Scanner) string {
	sc.Scan()
	return sc.Text()
}

func nextInt(sc *bufio.Scanner) (int, error) {
	return strconv.Atoi(nextText(sc))
}

Python: # -*- coding: utf-8 -*-
from collections import deque


class Graph:
    def __init__(self, n, adj_matrix):
        self.n = n
        self.adj_matrix = adj_matrix

    def show(self):
        for _ in self.adj_matrix:
            print(*_)

    def dfs(self):
        self.states = [2] * self.n
        self.d = [None] * self.n
        self.f = [None] * self.n
        self.time = 0

        for u in range(self.n):
            if self.states[u] == 2:
                self.dfs_visit(u)

    def dfs_visit(self, u):
        self.states[u] = 1
        self.time += 1
        self.d[u] = self.time

        for v, edge in [(v, edge) for v, edge in enumerate(self.adj_matrix[u])
                        if edge]:
            if self.states[v] == 2:
                self.dfs_visit(v)

        self.states[u] = 0
        self.time += 1
        self.f[u] = self.time

    def show_dfs(self, start=0):
        self.dfs()
        for i, (d, f) in enumerate(zip(self.d, self.f)):
            print(i + 1, d, f)

    def bfs(self, start):
        self.states = [1] * self.n
        self.dists = [float('inf')] * self.n

        queue = deque([start])
        self.dists[start] = 0
        while queue:
            u = queue.popleft()
            edges = self.adj_matrix[u]

            for v, edge in [(v, edge) for v, edge in enumerate(edges) if edge]:
                if v == start:
                    continue

                if self.dists[v] > self.dists[u] + 1:
                    self.dists[v] = self.dists[u] + 1
                queue.append(v)

        self.dists = [
            -1 if dist == float('inf') else dist for dist in self.dists
        ]

    def show_bfs(self, start=0):
        self.bfs(start=start)
        for i, dist in enumerate(self.dists):
            print(i + 1, dist)


if __name__ == '__main__':
    n = int(input())
    adj_matrix = [[0] * n for i in range(n)]
    for i in range(n):
        for v in input().split()[2:]:
            adj_matrix[i][int(v) - 1] = 1

    g = Graph(n, adj_matrix)
    g.show_bfs()

Python: from collections import deque
n = int(input())
G = [[] for _ in range(n)]
for i in range(n):
    u, k, *vs = map(int, input().split())
    u -= 1
    vs = list(map(lambda x: x - 1, vs))
    for v in vs:
        G[u].append(v)

dist = [-1] * n
dist[0] = 0
que = deque([0])

while len(que) > 0:
    now_v = que.popleft()
    now_dist = dist[now_v]
    next_vs = G[now_v]
    for next_v in next_vs:
        if dist[next_v] == -1:
            dist[next_v] = now_dist + 1
            que.append(next_v)

for i, x in enumerate(dist):
    print(i + 1, x)

Python: import queue


def bfs(g, s=1):
    global q

    dist = [-1] * len(g)
    dist[1] = 0
    q = queue.Queue()
    q.put(s)

    while not q.empty():
        v = q.get()
        if not G[v][1]:
            continue
        for vi in G[v][2:]:
            if dist[vi] >= 0:
                continue
            q.put(vi)
            dist[vi] = dist[v] + 1

    return dist


n = int(input())
G = [None]
for i in range(n):
    G.append(list(map(int, input().split())))

d = bfs(G)
for i in range(1, n + 1):
    print('%d %d' % (i, d[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 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: # -*- coding: utf-8 -*-

import sys
import os
import math


N = int(input())

E = []
E.append([])
d = [-1] * (N + 1)

for i in range(N):
    lst = list(map(int, input().split()))
    nodes = lst[2:]
    E.append(nodes)
#print(E)

q = []
q.append(1)

visited = [False] * (N + 1)
d[1] = 0
visited[1] = True

while q:
    index = q.pop(0)

    # ???????????????????????´???
    for v in E[index]:
        if not visited[v]:
            q.append(v)
            d[v] = d[index] + 1
            visited[v] = True

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

Python: 
import queue

WHITE = 0
GRAY = 1
BLACK = 2

NIL = -1
INF = 1000000000


def bfs(u):
    global Q
    Q.put(u)
    for i in range(n):
        d[i] = NIL
    d[u] = 0
    while not Q.empty():
        u = Q.get()
        for v in range(n):
            if (m[u][v] == 1) and (d[v] == NIL):
                d[v] = d[u] + 1
                Q.put(v)
n = int(input())

m = [[0 for i in range(n + 1)] for j in range(n + 1)]
vid = [0] * n
d = [0] * n
f = [0] * n
Q = queue.Queue()
color = [WHITE] * n
time = 0
nt = [0] * n

tmp = []
for i in range(n):
    nums=list(map(int,input().split()))
    tmp.append(nums)
    vid[i] = nums[0]

for i in range(n):
    for j in range(tmp[i][1]):
        m[i][vid.index(tmp[i][j + 2])] = 1

bfs(0)

for i in range(n):
    print(vid[i], d[i])

Python: from collections import deque
N = input()
d = [float('inf')] * N
m = [[0] * N for i in range(N)]
Q = deque([])

def bfs(s):
    Q.append(s)
    d[s] = 0

    while(len(Q) != 0):
        u = Q.popleft()
        for v in range(N):
            if (m[u][v] and  d[v] == float('inf')):
                d[v] = d[u] + 1
                Q.append(v)




if __name__ == '__main__':

    for i in range(N):
        v = map(int, raw_input().split())
        for j in v[2:]:
            m[i][j-1] = 1
    
    bfs(0)

    for i in range(N):
        if d[i] == float('inf'):
            d[i] = -1
        print (i+1), d[i]

Python: from collections import deque

N = 100
n = 0
M = None
WHITE = 0
GRAY = 1
BLACK = 2
INF = float('inf')
d = None


def main():
    global n, M, d
    M = [[0 for _ in range(N)] for _ in range(N)]
    n = int(input())
    d = [INF for _ in range(n)]

    for _ in range(n):
        u, k, *v_s = map(int, input().split(' '))
        for j in range(k):
            M[u-1][v_s[j-1]-1] = 1

    bfs()

    for i in range(n):
        print('{} {}'.format(i+1, d[i] if d[i] != INF else -1))


def bfs():
    q = deque()
    q.appendleft(0)
    d[0] = 0

    while len(q) > 0:
        u = q.pop()
        for v in range(n):
            if M[u][v] == WHITE:
                continue
            if d[v] != INF:
                continue
            d[v] = GRAY
            d[v] = d[u] + 1
            q.appendleft(v)


if __name__ == '__main__':
    main()