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: # -*- coding: utf-8 -*-

import sys
sys.setrecursionlimit(10 ** 9)
def input(): return sys.stdin.readline().strip()
def INT(): return int(input())
def MAP(): return map(int, input().split())
def LIST(): return list(map(int, input().split()))
INF=float('inf')

N=INT()
nodes=[[] for i in range(N)]
for i in range(N):
    l=LIST()
    u=l[0]
    l=l[2:]
    for v in l:
        nodes[u-1].append(v-1)
    nodes[u-1].sort()

ans=[[0]*2 for i in range(N)]
visited=[False]*N
time=0
def rec(u):
    if visited[u]:
        return
    visited[u]=True
    global time
    time+=1
    ans[u][0]=time
    for v in nodes[u]:
        rec(v)
    time+=1
    ans[u][1]=time

rec(0)
for i in range(N):
    d,f=ans[i]
    print(i+1, d, f)

Python: #!/usr/bin/python3

def find(A, id, V, time):
    i = id - 1
    A[i][0] = True
    A[i][1] = time
    time += 1
    for v in V[i]:
        if A[v - 1][0] == False:
            time = find(A, v, V, time)
    A[i][2] = time
    time += 1
    return time

n = int(input())
# [isFind, d, f]
A = [[False, 0, 0] for i in range(n)]
U = []
V = []
for i in range(n):
    l = list(map(int, input().split()))
    U.append(l[0])
    V.append(l[2:])

time = 1
for u in U:
    if A[u - 1][0] == False:
        time = find(A, u, V, time)

for u in U:
    l = [u]
    l.extend(A[u - 1][1:])
    print(' '.join(map(str, l)))

Python: def MAIN():
    n = int(input())
    ans = [[i, 0, 0] for i in range((n + 1))]
    G = [[] for _ in range((n + 1))]
    for _ in range(n):
        u, k, *v = map(int, input().split())
        G[u] = v
    cnt = 1
    def dfs(u):
        nonlocal ans
        if ans[u][1] != 0:
            return
        nonlocal cnt
        ans[u][1] = cnt
        cnt += 1
        for v in G[u]:
            dfs(v)
        ans[u][2] = cnt
        cnt += 1
    for i in range(1, n + 1):
        if ans[i][1] == 0:
            dfs(i)
        print(*ans[i])
MAIN()

Python: time=1
n=int(input())

A=[[] for i in range(n)]
d=[0 for i in range(n)]
f=[0 for i in range(n)]

for i in range(n):
	a=list(map(int,input().split()))
	for j in range(a[1]):
		A[i].append(a[2+j]-1)

def dfs(q,num):
	global d,f,time
	d[num]=time
	for nx in q[num]:
		if d[nx]==0:
			time+=1
			dfs(q,nx)
	time+=1
	f[num]=time
	
for i in range(n):
	if d[i]==0:#unvisit
		dfs(A,i)

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

Python: N = 100
WHITE = 0
GRAY = 1
BLACK = 2

d = [-1] * N
f = [-1] * N

def dfs_visit(n, u, tt, color):
    global d
    global f
    color[u] = GRAY
    tt += 1
    d[u] = tt
    for v in range(n):
        if M[u][v] == 0:
            continue
        if color[v] == WHITE:
            tt = dfs_visit(n, v, tt, color)
    color[u] = BLACK
    tt += 1
    f[u] = tt
    return tt

def dfs(n):
    global d
    global f
    color = []
    for u in range(n):
        color.append(WHITE)
    tt = 0

    for u in range(n):
        if color[u] == WHITE:
            tt = dfs_visit(n, u, tt, color)
    
    for u in range(n):
        print(u+1, d[u], f[u])

n = int(input())

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

for i in range(n):
    I = list(map(int, input().split()))
    u = I[0] - 1
    k = I[1]
    for j in range(k):
        v = I[j+2] - 1
        M[u][v] = 1

#print(M)

dfs(n)

Python: n = int(input())

m = [[0 for i in range(n)] for j in range(n)]

for i in range(n):
    com = list(map(int, input().split()))
    for j in range(com[1]):
        m[i][com[j+2]-1] = 1

color = ["white" for i in range(n)]

d = [0 for i in range(n)]
f = [0 for i in range(n)]
time = 0

def dfs(u):
    global time
    time += 1
    color[u] = "gray"
    d[u] = time
    for i in range(u, n):
        if m[u][i] and color[i] == "white":
            dfs(i)
    color[u] = "black"
    time += 1
    f[u] = time

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

Python: import sys
sys.setrecursionlimit(2000000)

n = int(input())
m = [list(map(int, input().split()))[2:] for _ in range(n)]

def dfs(x, time):
    first[x] = time
    time += 1
    for v in m[x]:
        if first[v-1] == 0:
            time = dfs(v-1, time)
    finish[x] = time
    time += 1
    return time

first = [0] * n
finish = [0] * n

time = 1
for i in range(n):
    if first[i] == 0:
        time = dfs(i, time)

for i, xy in enumerate(zip(first, finish)):
    print(i+1, *xy)

Python: #16D8101014F KurumeRyunosuke 2018/6/20

n=int(input())
ls=[[0 for i in range(n)]for j in range(n)]
for i in range(n):
	tmp=input().split()
	for j in range(int(tmp[1])):
		ls[i][int(tmp[j+2])-1]=1

"""
for i in range(n):
    for j in range(n):
        if(j!=n-1):
            print(int(ls[i][j]), end=' ')
        else:
            print(int(ls[i][j]))
"""
stuck=[0]
count=1
d=[0 for i in range(n)]
f=[0 for i in range(n)]
d[0]=count
while True:
	count+=1
	p=0
	for i in range(n):
		if ls[stuck[len(stuck)-1]][i] is not 0:
			ls[stuck[len(stuck)-1]][i]=0
			
			p=1
			#print(stuck)
			stuck.append(i)
			d[stuck[len(stuck)-1]]=count
			break

	if p is 1:
		for i in range(n):
			ls[i][stuck[len(stuck)-1]]=0
	if p is 0:
		#print("//")
		a=stuck.pop()
		f[a]=count
		for i in range(n):
			ls[a][i]=0

	if len(stuck) is 0:
		t=0
		for i in range(n):
			for j in range(n):
				if ls[i][j] is not 0 and t is 0:
					count+=1
					stuck.append(i)
					d[stuck[len(stuck)-1]]=count
					#print(i)
					t=1
					
		if t is 0:
			break
		#print("break")

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