Go: package main

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

// I/O
type Scanner struct {
	sc *bufio.Scanner
}

func NewScanner() *Scanner {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)
	sc.Buffer(make([]byte, 1024), int(1e+9))
	return &Scanner{sc}
}

func (s *Scanner) nextStr() string {
	s.sc.Scan()
	return s.sc.Text()
}

func (s *Scanner) nextInt() int {
	i, e := strconv.Atoi(s.nextStr())
	if e != nil {
		panic(e)
	}
	return i
}

func (s *Scanner) nextFloat() float64 {
	f, e := strconv.ParseFloat(s.nextStr(), 64)
	if e != nil {
		panic(e)
	}
	return f
}

func (s *Scanner) nextRuneSlice() []rune {
	return []rune(s.nextStr())
}

func (s *Scanner) nextIntSlice(n int) []int {
	res := make([]int, n)
	for i := 0; i < n; i++ {
		res[i] = s.nextInt()
	}
	return res
}

func (s *Scanner) nextFloatSlice(n int) []float64 {
	res := make([]float64, n)
	for i := 0; i < n; i++ {
		res[i] = s.nextFloat()
	}
	return res
}

// Arithmetic
func max(nums ...int) int {
	m := nums[0]
	for _, i := range nums {
		if m < i {
			m = i
		}
	}
	return m
}

func min(nums ...int) int {
	m := nums[0]
	for _, i := range nums {
		if m > i {
			m = i
		}
	}
	return m
}

func abs(x int) int {
	if x > 0 {
		return x
	}
	return -x
}

func pow(x, y int) int {
	res := 1
	for i := 0; i < y; i++ {
		res *= x
	}
	return res
}

func ceil(a, b int) int {
	if a%b == 0 {
		return a / b
	} else {
		return a/b + 1
	}
}

// Sort
type RuneSlice []rune

func (a RuneSlice) Len() int           { return len(a) }
func (a RuneSlice) Less(i, j int) bool { return a[i] < a[j] }
func (a RuneSlice) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }

// Main
type Queue struct {
	arr []int
}

func (q *Queue) push(v int) {
	q.arr = append(q.arr, v)
}

func (q *Queue) pop() int {
	res := q.arr[0]
	q.arr = q.arr[1:]
	return res
}

func (q *Queue) isEmpty() bool {
	return len(q.arr) == 0
}

func main() {
	sc := NewScanner()
	wtr := bufio.NewWriter(os.Stdout)
	N := sc.nextInt()
	G := make([][]int, N)
	for i := 0; i < N; i++ {
		u, k := sc.nextInt()-1, sc.nextInt()
		for j := 0; j < k; j++ {
			G[u] = append(G[u], sc.nextInt()-1)
		}
	}
	var q Queue
	seen := make([]int, N)
	for i := 0; i < N; i++ {
		seen[i] = -1
	}
	var search func(cur int)
	search = func(cur int) {
		for i := 0; i < len(G[cur]); i++ {
			next := G[cur][i]
			if seen[next] == -1 {
				q.push(next)
				seen[next] = seen[cur] + 1
			}
		}
	}
	q.push(0)
	seen[0] = 0
	for !q.isEmpty() {
		search(q.pop())
	}

	for i := 0; i < N; i++ {
		fmt.Fprintln(wtr, i+1, seen[i])
	}
	wtr.Flush()
}

Python: from collections import deque


def bfs(s, m, n):
    d = []
    for _ in range(n):
        d.append(1 << 21)
    queue = deque()
    queue.append(s)
    d[s] = 0

    while len(queue) != 0:
        u = queue.popleft()
        for v in range(n):
            if m[u][v] == 0:
                continue
            if d[v] != 1 << 21:
                continue
            d[v] = d[u] + 1
            queue.append(v)

    for i, v in enumerate(d):
        ans_v = v
        if v == 1 << 21:
            ans_v = -1

        print(i + 1, ans_v)


n = int(input())
m = list()
for i in range(n):
    tmp = list()
    for j in range(n):
        tmp.append(0)
    m.append(tmp)

for _ in range(n):
    l = [int(i) for i in input().split()]
    u = l[0]
    for li in l[2:]:
        m[u - 1][li - 1] = 1

bfs(0, m, n)

Python: N= int(input())
E = [input().split()[2:] for _ in range(N)]
frag, T, L,Q = [0]*N, [0]*N,[0] + [-1]*N, [0]
frag[0] = 1
def func(ide):
    for i in E[ide]:
        i = int(i) - 1
        if L[i] < 0 :frag[i] = 1;L[i] = L[ide] +1 ;Q.append(i) 
        else:return

while Q:top = Q.pop();func(top)

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

Python: import queue

n = int(input())
graph = []
for _ in range(n):
    line = list(map(int, input().split()))
    graph.append([v - 1 for v in line[2:]])

q = queue.Queue()
q.put(0)
dist = [-1] * n
dist[0] = 0

while True:
    v = q.get()
    for next_v in graph[v]:
        if dist[next_v] == -1: 
            q.put(next_v)
            dist[next_v] = dist[v] + 1

    if q.empty():
        break

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

Python: n = int(input())

adj = [None]
for i in range(n):
    adj_i = list(map(int, input().split()[2:]))
    adj.append(adj_i)

isSearched = [None] + [False] * n

distance = [None] + [-1] * n

import collections

def bfs(u):
    isSearched[u] = True
    distance[u] = 0
    edge = collections.deque()
    edge.append(u)
    while edge:
        c_e = edge.popleft()
        for n_e in adj[c_e]:
            if not isSearched[n_e]:
                isSearched[n_e] = True
                distance[n_e] = distance[c_e] + 1
                edge.append(n_e)


bfs(1)

for i, x in enumerate(distance[1:], start=1):
    print(i, x)

Python: n = int(input())
g = [input().split()[2:] for _ in range(n)]

from collections import deque
que = deque()
que.append(0)
d = [0] + [-1] * n

while que:
    u = que.popleft()

    for v in g[u]:
        v = int(v) - 1

        if d[v] < 0:
            d[v] = d[u] + 1
            que.append(v)

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

"""
・グラフの数を受け取る
・グラフを作る．今回は隣接リストで必要な部分だけを残してリスト化する
・キュー用の配列を作る（これはなんでもいい．普通のリストでも可）．そのキューには1番初めのスタート位置を入れておく
・最短距離を置いておくリストを用意
・queの中身がなくなるまで続ける
・queの中身を取り出して，それにくっついてるノードを全て舐めていく．int方で入力を受け取っていないから注意．1-indexを0-indexに変える．
・もしそこにまだBFSが訪れていなかったら，そこに前回の場所から1足した物を代入
・探索用のqueに追加しておく．追加しておくことでまたそのノードとつながってるところを調べることができる
・最後は出力．全てのノードの最短距離を出力
"""

Python: from collections import deque

n = int(input())
g = [None] * n
visited = [0] * n
dist = [-1] * n
Q = deque()

while n:
    l = list(map(int, input().split()))
    g[l[0]-1] = [i-1 for i in l[2:]]
    n -= 1

Q.append((0, 0)) 
visited[0] = 1

while Q:
    i, d = Q.popleft()         
    dist[i] = d
    for c in g[i]:
        if not visited[c]:
            visited[c] = 1
            Q.append((c, d+1))

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

Python: from collections import deque
if __name__ == "__main__":
    n = int(input())
    graph = []
    for _ in range(n):
        v, k, *tmp = map(int, input().split())
        for j in range(len(tmp)):
            tmp[j] -= 1
        graph.append(tmp)
    visited = [False] * n
    qu = deque()
    qu.appendleft((0, 0))
    ans = [-1] * n
    visited[0] = True

    while qu:
        now, dis = qu.pop()
        ans[now] = dis

        for nei in graph[now]:
            if not visited[nei]:
                visited[nei] = True
                qu.appendleft((nei, dis + 1))
    for i in range(n):
        print(i+1,ans[i])

Python: from collections import deque

n = int(input())
li = [list(map(int, input().split())) for _ in range(n)]

graph = [[] for _ in range(n+1)]
for u, k, *v in li:
    for i in v:
        graph[u].append(i)

ans = [-1] * (n+1)

ans[1] = 0
stack = deque([1])
while stack:
    num = stack.popleft()

    for s in graph[num]:
        if ans[s] == -1:
            stack.append(s)
            ans[s] = ans[num] + 1
            
for i, v in enumerate(ans[1:]):
    print(i+1, v)

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


if __name__ == '__main__':

    n = int(input())
    M = [[0 for i in range(n)] for j in range(n)]
    for _ in range(n):
        l = list(map(int, input().split(" ")))
        u = l[0]
        k = l[1]
        if k != 0:
            for v in l[2:]:
                M[u - 1][v - 1] = 1

    color = [0] * n
    d = [-1] * n
    Q = deque()

    def bfs(s):  # breadth-first search
        color[s] = 1
        d[s] = 0
        Q.append(s)

        while len(Q) != 0:
            u = Q.popleft()
            for v in range(n):
                if M[u][v] == 1 and color[v] == 0:
                    color[v] = 1
                    d[v] = d[u] + 1
                    Q.append(v)
            color[u] = 2

    bfs(0)
    for i in range(n):
        print(i + 1, d[i])