Go: package main

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

var scanner = bufio.NewScanner(os.Stdin)

func nextString() string {
	scanner.Scan()
	return scanner.Text()
}

func nextInt() int {
	n, err := strconv.Atoi(nextString())
	if err != nil {
		fmt.Printf("strconv.Atoi failed: %v\n", err)
	}
	return n
}

var infty = 1000000000

type nodeKey int

type DirectedGraphNode struct {
	key       nodeKey
	adjacents []*DirectedGraphNode
	visited   bool
	d         int
	f         int
	parent    *DirectedGraphNode
}

type DirectedGraph struct {
	nodes []*DirectedGraphNode
}

func (g *DirectedGraph) setAdjacency(l, r nodeKey) {
	g.nodes[l].adjacents = append(g.nodes[l].adjacents, g.nodes[r])
}

func newDirectedGraph(nNodes int) *DirectedGraph {
	graph := DirectedGraph{}
	graph.nodes = make([]*DirectedGraphNode, nNodes)
	for iNodes := 0; iNodes < nNodes; iNodes++ {
		graph.nodes[iNodes] = &DirectedGraphNode{}
		graph.nodes[iNodes].key = nodeKey(iNodes)

		graph.nodes[iNodes].visited = false
		graph.nodes[iNodes].d = infty
		graph.nodes[iNodes].f = infty
		graph.nodes[iNodes].parent = nil
	}
	return &graph
}

type QueueEntry struct {
	node *DirectedGraphNode
	next *QueueEntry
}

type Queue struct {
	head, tail *QueueEntry
}

func (q *Queue) enqueue(node *DirectedGraphNode) {
	entry := QueueEntry{}
	entry.node = node

	if q.tail == nil {
		q.head = &entry
		q.tail = &entry
		return
	}

	q.tail.next = &entry
	q.tail = q.tail.next
}

func (q *Queue) dequeue() *QueueEntry {
	if q.head == nil {
		return nil
	}
	poped := q.head
	q.head = q.head.next
	if q.head == nil {
		q.tail = nil
	}
	return poped
}

func (q *Queue) isEmpty() bool {
	return q.head == nil
}

var time = 0

func fillDistancesByDepthFirstSearch(g *DirectedGraph) {
	for _, u := range g.nodes[1:] {
		if !u.visited {
			dfsVisit(g, u)
		}
	}
}

func dfsVisit(g *DirectedGraph, u *DirectedGraphNode) {
	time++
	u.d = time

	u.visited = true
	for _, v := range u.adjacents {
		if !v.visited {
			v.parent = u
			dfsVisit(g, v)
		}
	}
	time++
	u.f = time
}

func main() {
	scanner.Split(bufio.ScanWords)

	nNodes := nextInt()
	g := newDirectedGraph(nNodes + 1)

	for iNode := 0; iNode < nNodes; iNode++ {
		nodeKeyLeft := nodeKey(nextInt())
		nAdj := nextInt()
		for iAdj := 0; iAdj < nAdj; iAdj++ {
			nodeKeyRight := nodeKey(nextInt())
			g.setAdjacency(nodeKeyLeft, nodeKeyRight)
		}
	}

	fillDistancesByDepthFirstSearch(g)

	for iNode := 1; iNode <= nNodes; iNode++ {
		node := g.nodes[iNode]
		fmt.Println(node.key, node.d, node.f)
	}
}

Python: N = int(input())

from collections import deque,defaultdict
G = defaultdict(deque)
for i in range(1,N+1):
    t = [int(i) for i in input().split(' ')]
    for j in range(t[1]):
        G[t[0]].append(t[j+2])

time = 1
arrive_time = [-1] * (N + 1) # 到着時刻
finish_time = [-1] * (N + 1) # 到着時刻

def dfs(G,s):
    global time
    stack = deque([s])
    arrive_time[s] = time
    while stack:
        t = stack[-1]
        if G[t]:
            w = G[t].popleft()
            if arrive_time[w] >= 0:
                continue
            elif w in stack:
                continue
            else:
                time += 1
                arrive_time[w] = time
                stack.append(w)
        else:
            time += 1
            finish_time[t] = time
            stack.pop()
            
    return arrive_time,finish_time

for i in range(1,N+1):
    if arrive_time[i] < 0:
        arrive,finish = dfs(G,i)
        time += 1

for i, (a, f) in enumerate(zip(arrive,finish)):
    if not i == 0:
        print(i,a,f)

Python: import heapq
from collections import deque
from enum import Enum
import sys
import math
from _heapq import heappush, heappop

BIG_NUM = 2000000000
MOD = 1000000007
EPS = 0.000000001

global current_time
global visited,go_time,back_time
global G


def dfs(node_id):
    global current_time #書かないとローカル変数扱いされる
    go_time[node_id] = current_time
    current_time += 1

    for next_node in G[node_id]:

        if visited[next_node] == True:
            continue
        visited[next_node] = True
        dfs(next_node)

    back_time[node_id] = current_time
    current_time += 1


V = int(input())

G = [[] for i in range(V)]

visited = [False]*V

go_time = [0]*V
back_time = [0]*V

for loop in range(V):
    node_id,num,*tmp_adj = list(map(int,input().split()))
    node_id -= 1
    for i in range(num):
        G[node_id].append(tmp_adj[i]-1)

current_time = 1;

for i in range(V):
    if visited[i] == True:
        continue
    visited[i] = True
    dfs(i)

for i in range(V):
    print("%d %d %d"%(i+1,go_time[i],back_time[i]))

Python: n = int(input())
g = []
for i in range(n):
    a = list(map(int,input().split()))
    g.append(a[2:])
d = [0]*n
f = [0]*n
global t
t = 1
d[0] = 1
x = 1
def find(x):
    global t
    if len(g[x-1]) == 0:
        t += 1
        f[x-1] = t
    else:
        for i in g[x-1]:
            if d[i-1] == 0:
                t += 1
                d[i-1] = t
                find(i)
        t += 1
        f[x-1] = t

find(x)
for i in range(n):
    if d[i] == 0:
        t += 1
        d[i] = t
        find(i+1)
for i in range(n):
    print(i+1, d[i], f[i])

Python: def depth(s, time):
    time += 1
    flag[s] = 1
    d[s] = t
    for i in range(1, n+1):
        if G[s][i] == 1:
            if flag[i] == 0:
                depth(i, time)
                t = f[i]
    f[s] = time + 1
 
n = int(raw_input())
G = [[0 for i in range(n+1)] for j in range(n+1)]
d = [0 for i in range(n+1)]
f = [0 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)]
for i in range(1, n+1):
    if flag[i] == 0:
        depth(i, max(f))
 
for i in range(1, n+1):
    print(str(i) + " " + str(d[i]) + " " + str(f[i]))

Python: n = int(input())
adj = [[None for _ in range(n)] for _ in range(n)]
for i in range(n):
    l = list(map(int, input().split()))
    if l[1] == 0:
        continue 
    else:
        for j in range(2,len(l)):
            adj[l[0]-1][l[j]-1] = 1
color = ['white' for _ in range(n)]
d = [None for _ in range(n)]
f = [None for _ in range(n)]
time = 1

def dfs(node):
    global color
    global d 
    global f
    global time 
    S = [node]
    color[node -1] = 'grey'
    d[node -1] = time 
    while S:
        u = S[-1]
        v = 1
        while v <= n:
            if adj[u-1][v-1] == 1 and color[v-1] == 'white':
                break
            v += 1
        if v < n+1:
            color[v-1] = 'grey'
            time += 1
            d[v-1] = time 
            S.append(v)
        else:
            time += 1
            S.pop()
            color[u-1] = ['black']
            f[u-1] = time

for node in range(1, n+1):
    if color[node-1] == 'white':
        dfs(node)
        time += 1
for i in range(n):
    print(' '.join([str(i+1), str(d[i]), str(f[i])]))

Python: ii = lambda : int(input())
mi = lambda : map(int,input().split())
li = lambda : list(map(int,input().split()))

class tree:
    def __init__(self,n):
        self.n = n
        self.vlist = [None]*self.n
        self.start = [None]*self.n
        self.finish = [None]*self.n
        self.time = 0
    
    def add(self,n,v):
        v.sort()
        self.vlist[n] = v

    def search(self,u):
        if self.start[u] != None:
            return
        else:
            self.time += 1
            self.start[u] = self.time

            for i in self.vlist[u]:
                self.search(i-1)

            self.time += 1
            self.finish[u] = self.time
            return

n = ii()
t = tree(n)

for i in range(n):
    vk = li()
    u = vk[0]
    k = vk[1]
    v = vk[2:]
    t.add(u-1,v)

for i in range(n):
    t.search(i)

for i in range(n):
    print(i+1, t.start[i], t.finish[i])