Go: package main

/*
グラフの表現 隣接行列による表現
*/

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

func main() {
	scanner := makeScanner(8192)
	n := eGetInt(scanner)
	g := make([][]int, n+1)
	for i := 1; i < n+1; i++ {
		g[i] = make([]int, n+1)
		ints := eGetInts(scanner)
		num := ints[0]
		for j := 0; j < ints[1]; j++ {
			g[num][ints[j+2]] = 1
		}
	}
	dist := make([]int, n+1)
	for i := 0; i < len(dist); i++ {
		dist[i] = -1
	}
	q := []int{}

	// 訪問する
	q = append(q, 1)
	dist[1] = 0

	// キューが空でない限り
	for len(q) > 0 {
		// 先頭を取り出す
		top := 0
		top, q = q[0], q[1:]
		// 隣接マスを入れる.
		for i := 1; i < n+1; i++ {
			// 辺がある
			if g[top][i] == 1 {
				if dist[i] == -1 {
					// 訪問済みでなければ
					q = append(q, i)
					dist[i] = dist[top] + 1
				}
			}
		}
	}
	for i := 1; i < n+1; i++ {
		fmt.Println(i, dist[i])
	}
}

////////////////////////////////////////////////////////////////////////////////
// ライブラリ
////////////////////////////////////////////////////////////////////////////////
func makeScanner(maxByte int) *bufio.Scanner {
	scanner := bufio.NewScanner(os.Stdin)
	scanner.Buffer(make([]uint8, 0, 8192), maxByte)
	return scanner
}
func makeWordScanner() *bufio.Scanner {
	scanner := makeScanner(8192)
	scanner.Split(bufio.ScanWords)
	return scanner
}
func eGetLine(r *bufio.Scanner) string {
	if r.Scan() {
		return r.Text()
	}
	err := r.Err()
	if err != nil {
		log.Fatal(err)
	}
	// EOF
	return ""
}
func eGetInt(r *bufio.Scanner) int {
	line := eGetLine(r)
	return eAtoi(line)
}
func eGetInt64(r *bufio.Scanner) int64 {
	line := eGetLine(r)
	return eAtoInt64(line)
}
func eGetFields(r *bufio.Scanner) []string {
	line := eGetLine(r)
	return strings.Fields(line)
}
func eGetInts(r *bufio.Scanner) []int {
	fields := eGetFields(r)
	ints := make([]int, len(fields))
	for i := 0; i < len(ints); i++ {
		ints[i] = eAtoi(fields[i])
	}
	return ints
}
func eGetInt64s(r *bufio.Scanner) []int64 {
	fields := eGetFields(r)
	ints := make([]int64, len(fields))
	for i := 0; i < len(ints); i++ {
		ints[i] = eAtoInt64(fields[i])
	}
	return ints
}
func eGetChars(r *bufio.Scanner) []string {
	line := eGetLine(r)
	return strings.Split(line, "")
}
func eAtoi(s string) int {
	n, err := strconv.Atoi(s)
	if err != nil {
		log.Fatal(err)
	}
	return n
}
func eAtoInt64(s string) int64 {
	n, err := strconv.ParseInt(s, 10, 64)
	if err != nil {
		log.Fatal(err)
	}
	return n
}

Python: 
def bfs(s):  # たぶんstartのs
    global n, M, color, d, q

    q.append(s)
    d[s] = 0

    while len(q) != 0:
        u = q.pop(0)

        for v in range(n):
            if M[u][v] != 1:
                continue

            if color[v] == 'WHITE':
                q.append(v)
                color[v] = 'GRAY'
                d[v] = d[u] + 1

        color[u] = 'BLACK'


n = int(input())

M = [[0 for i in range(n)] for j in range(n)]
color = ['WHITE'] * n  # 各頂点の色を記録。ホワイト（未探索）、グレイ（探索中）、ブラック（探索ずみ）
d = [-1] * n  # 始点0からvまでの距離
q = []

for i in range(n):
    _ = list(map(int, input().split()))
    u = _[0] - 1  # 0オリジンに変換

    degree = _[1]
    for j in range(degree):
        v = _[j+2] - 1  # 0オリジンに変換
        M[u][v] = 1

# for row in M:
#     print(' '.join(map(str, row)))

bfs(0)

for i in range(n):
    print('{} {}'.format(i+1, d[i]))

Python: N= int(input());E = [input().split()[2:] for _ in range(N)]
frag, T, L,Q = [0]*N, [0]*N, [0]*N, [0]
a,frag[0] = 100, 1
def func(ide):
    for i in E[ide]:
        i = int(i) - 1
        if frag[i] != 1:frag[i] = 1;L[i] = L[ide] +1 ;Q.append(i) 
        else:return

while Q:top = Q[0];func(top);del Q[0]
for i in range(n):
    if L[i] == 0:
        L[i] == -1

for i in range(N):print(i + 1 ,int(L[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 = [1000 for i in range(n)]
dis[0] = 0

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:
       if dis[k] > dis[s] + 1:
         dis[k] = dis[s] + 1
         bfs_visit(k)

for s in range(n):
    bfs_visit(s)
for s in range(n):
    if dis[s] == 1000:
       dis[s] = -1
for s in range(n):
    print (s+1,dis[s])

Python: from collections import deque
N = int(input())
#グラフ入力受取
G = [[] for _ in range(N)]
for _ in range(N):
    a = list(map(int, input().split()))
    for i in a[2:]:
        G[a[0]-1].append(i-1)

#頂点1をスタートとした探索
dist = [-1]*N
que = deque()
dist[0] = 0
que.append(0)
while len(que)!=0:
    v = que.popleft()
    for nv in G[v]:
        if dist[nv] == -1:
            dist[nv] = dist[v]+1
            que.append(nv)
        
for i in range(N):
    print(str(i+1) + ' ' + str(dist[i]))

Python: from collections import deque


INFINITY = 10 ** 10
WHITE = 0
GRAY = 1
BLACK = 2


def breadth_first_search(u_start = 0):
    color[u_start] = GRAY
    d[u_start] = 0
    que.append(u_start)

    while que:
        u = que.popleft()
        for v in range(n):
            if matrix[u][v] and color[v] == WHITE:
                color[v] = GRAY
                d[v] = d[u] + 1
                que.append(v)
        color[u] = BLACK


# INPUT
n = int(input())


matrix = [[0] * n for _ in range(n)]

for i in range(n):

    u, k, *V = map(int, input().split())

    for v in V:
        v -= 1
        matrix[i][v] = 1


color = [WHITE] * n
d = [INFINITY] * n
que = deque([])

# PROCESS
breadth_first_search()


# OUTPUT
for i in range(n):
    if d[i] == INFINITY:
        distance = -1
    else:
        distance = d[i]

    print(i + 1, distance)

Python: # https://onlinejudge.u-aizu.ac.jp/courses/lesson/1/ALDS1/11/ALDS1_11_C
# 実家のような安心感
# 与えられるノード番号についてはすべて0based indexに治す

from collections import deque

# データの入力
N = int(input())
DG = {}
for i in range(N):
    tmp = input().split()
    if int(tmp[1]) != 0:
        DG[i] = [int(x)-1 for x in tmp[2:]]
    else:
        DG[i] = []


result = {}
is_visited = {key: False for key in range(N)}
# bfs
# 初期queue
que = deque([(0, 0)])  # 必要なものはnodeidと原点からの距離
while que:
    nodeid, cost = que.popleft()  # 先入れ先出し
    result[nodeid] = cost
    is_visited[nodeid] = True  # この文は最初の1for目しか意味ないんだけどなんかうまい方法ないのか
    for nextnode in DG[nodeid]:
        if is_visited[nextnode]:
            pass
        else:  # 未訪問のものについては探索候補に入れる
            que.append((nextnode, cost + 1))
            is_visited[nextnode] = True  # 探索候補に入れた瞬間に訪問管理しないと重複を生じる場合がある

for i in range(N):
    if is_visited[i]:
        print(i + 1, result[i])
    else:
        print(i+1, -1)

Python: N= int(input())
E = [input().split()[2:] for _ in range(N)]
frag, T, L,Q = [0]*N, [0]*N, [0]*N, [0]
a,frag[0] = 100, 1
def func(ide):
    for i in E[ide]:
        i = int(i) - 1
        if frag[i] != 1:frag[i] = 1;L[i] = L[ide] +1 ;Q.append(i) 
        else:return

while Q:top = Q[0];func(top);del Q[0]
for i in range(n):
    if L[i] == 0:
        L[i] == -1

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

Python: from collections import deque

N = int(input())

nodes = [tuple(map(int, input().split(' '))) for _ in range(N)]

distances = [-1] * (N + 1)

queue = deque()
queue.append((1, 0))

while len(queue) > 0:
    node, distance = queue.popleft()
    if distances[node] != -1:
        continue
    distances[node] = distance

    neighbors = nodes[node - 1][2:]
    for neighbor in neighbors:
        queue.append((neighbor, distance + 1))

for node in range(1, N + 1):
    print(node, distances[node])

Python: #coding: utf-8
inf = 100000000
n = int(input())

List = [0] + [list(map(int,input().split())) for i in range(n)]
color = [0] + ["white" for  i in range(n)]
d = [inf for i in range(n+1)]

s = 1
Q = [s]
d[s] = 0
while Q != []:
    q = Q.pop()
    if color[q] == "white":
        k = List[q][1]
        if k != 0:
            Q += List[q][2:2+k]
            for i in List[q][2:2+k]:
                d[i] = min(d[q] + 1, d[i])
    
    color[q] = "black"


for i, dis in enumerate(d[1:], 1):
    if dis == inf:
        dis = -1
    print(i, dis)