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

Python: from collections import deque

n = int(input())
graph = [[] for _ in range(n + 1)]
for _ in range(n):
    input_list = list(map(int, input().split()))
    index = input_list[0]
    num = input_list[1]

    if num >= 1:
        nodes = input_list[2:]
        for node in nodes:
            graph[index].append(node)
            # graph[node].append(index)

visited = [-1] * (n + 1)
num = [-1] * (n + 1)
q = deque()
visited[1] = 1
num[1] = 0
q.append(1)

while q:
    index = q.popleft()
    
    for node in graph[index]:
        if visited[node] == -1:
            visited[node] = 1
            num[node] = num[index] + 1
            q.append(node)


for i, j in enumerate(num):
    if i == 0:
        continue
    print(i, j)

Python: N= int(input())
E = [input().split()[2:] for _ in range(N)]
frag, T, L,Q = [0]*N, [0]*N, [0]*N, [0]
frag[0] = 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(1,N):
    if int(L[i]) == 0:
        L[i] = -1

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

Python: #from collections import deque
import sys

readline = sys.stdin.readline
sys.setrecursionlimit(10**6)

#def mypopleft(que, index):
#    if len(que) > index:
#        return que.pop(index)
#    else:
#        return []


def main():
    # input
    n = int(input())

    graph = []
    for i in range(n):
        u, k, *tmp = [int(i) for i in readline().split()]
        graph.append(tmp)
    
    #print(graph)
    d = [-1]*n
    #que = deque([1])
    que = [1]
    #count = 0
    d[0] = 0
    check = []

    while True:
        v = que.pop(0)
        #print(v)
        #count += 1
        #print(d)
        for u in graph[v-1]:
            #print(u)
            if d[u-1] == -1:
                d[u-1] = d[v-1] + 1
                que.append(u)
        if len(que) == 0:
            break
    
    for i in range(n):
        print("{} {}".format(i+1, d[i]))


if __name__ == "__main__":
    main()

Python: from sys import maxsize


def read_adj():
    n = int(input())
    adj_list = [[] for _ in range(n + 1)]
    for _ in range(1, n + 1):
        u, _, *adj = [int(x) for x in input().split()]
        adj_list[u] = adj
    return n, adj_list


def shortest_paths(n, adj_list, ini_key):
    dist = [maxsize] * (n + 1)

    S = [ini_key]
    dist[ini_key] = 0

    while S != []:
        key = S.pop()
        d = dist[key] + 1
        for k in adj_list[key]:
            if d < dist[k]:
                dist[k] = d
                S.append(k)

    return dist


def print_dist(n, dist):
    for i in range(1, n + 1):
        if dist[i] == maxsize:
            print(i, -1)
        else:
            print(i, dist[i])


def main():
    n, adj_list = read_adj()
    dist = shortest_paths(n, adj_list, 1)
    print_dist(n, dist)


if __name__ == '__main__':
    main()

Python: n = int(input())
G = {}
D = [-1] * n
for _ in range(n):
    A = list(map(int, input().split()))
    G[A[0] - 1] = [a - 1 for a in A[2:]]

# print(G)

q = [(0, 0)]
while len(q) > 0:
    v, d = q[0]
    del q[0]
    if D[v] >= 0:
        continue
    D[v] = d

    for nv in G[v]:
        q.append((nv, d+1))

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

Python: from collections import deque

N = int(input())
graph = {i:[] for i in range(N)}

for i in range(N):
    g = list(map(int, input().split()))
    for j in range(g[1]):
        graph[g[0]-1].append(g[j+2]-1)
        
que = deque()
dist = [-1 for _ in range(N)]
que.append(0)
dist[0] = 0

while que:
    top = que.popleft()
    
    for i in graph[top]:
        if(dist[i] != -1):
            continue
        dist[i] = dist[top]+1
        que.append(i)

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

Python: n = int(input())
v = []
for i in range(n):
    v_i = list(map(int,input().split()))[2:]
    v.append(v_i)
    
d = [-1]*n
d[0]=0
queue = [1]
dis = 1
while len(queue)!=0:
    queue2 = []
    for i in queue:
        for nex in v[i-1]:
            if d[nex-1]==-1:
                d[nex-1]=dis
                queue2.append(nex)
    dis +=1
    queue = queue2

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