Go: package main

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

type TimeRecord struct {
	discoverTime int
	finishTime   int
}

func main() {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)

	n, err := nextInt(sc)
	if err != nil {
		panic(err)
	}

	timeRecordMap := make([]TimeRecord, n)
	childrenMap := make([][]int, n)
	for i := 1; i <= n; i++ {
		node, err := nextInt(sc)
		if err != nil {
			panic(err)
		}
		timeRecordMap[node-1] = TimeRecord{-1, -1}

		childNum, err := nextInt(sc)
		if err != nil {
			panic(err)
		}
		childrenMap[node-1] = make([]int, childNum)
		for j := 0; j < childNum; j++ {
			child, err := nextInt(sc)
			if err != nil {
				panic(err)
			}
			childrenMap[node-1][j] = child
		}
	}

	timer := 1
	for {
		startNode := findStartNode(childrenMap, timeRecordMap)
		if startNode > 0 {
			visit(startNode, &timer, childrenMap, timeRecordMap)
		} else {
			break
		}
	}
	for k, v := range timeRecordMap {
		fmt.Printf("%d %d %d\n", k+1, v.discoverTime, v.finishTime)
	}
}

func findStartNode(childrenMap [][]int, timeRecordMap []TimeRecord) int {
	x := -1
	for node, timeRecord := range timeRecordMap {
		if timeRecord.discoverTime < 0 {
			x = node + 1
			break
		}
	}
	if x < 0 {
		return -1
	}

	found := false
	i := 0
	for i < len(childrenMap) {
		children := childrenMap[i]
		for j := 0; j < len(children); j++ {
			if children[j] == x {
				x = j + 1
				found = true
				break
			}
		}
		if found {
			i = 0
		} else {
			i++
		}
	}
	return x
}

func visit(currentNode int, timer *int, childrenMap [][]int, timeRecordMap []TimeRecord) {
	if timeRecordMap[currentNode-1].discoverTime > 0 {
		return
	}
	children := childrenMap[currentNode-1]
	timeRecordMap[currentNode-1] = TimeRecord{*timer, timeRecordMap[currentNode-1].finishTime}
	(*timer)++
	for i := 0; i < len(children); i++ {
		visit(children[i], timer, childrenMap, timeRecordMap)
	}
	timeRecordMap[currentNode-1] = TimeRecord{timeRecordMap[currentNode-1].discoverTime, *timer}
	(*timer)++
}

func nextInt(sc *bufio.Scanner) (int, error) {
	sc.Scan()
	return strconv.Atoi(sc.Text())
}

Python: G = {}
for _ in range(int(input())):
  x = list(map(int, input().split()))
  G[x[0]] = sorted(x[2:])

t = 1
stack = [1]
timestamp = {1:[t]}

while len(stack) > 0:
  t += 1
  v = stack[-1]

  while len(G[v]) > 0:
    v = G[v].pop(0)
    if v in timestamp: continue
    stack.append(v)
    timestamp[v] = [t]
    break
  else:
    v = stack.pop()
    timestamp[v].append(t)

for i in timestamp:
  print(i, *timestamp[i])

Python: import sys

time = 0
def dfs(u):
    global time
    flag_list[u] = 1
    time += 1
    d_list[u] = time
    for v in range(n):
        if m_list[u][v] == 1 and flag_list[v] == 0:
            dfs(v)
    flag_list[u] = 2
    time += 1
    f_list[u] = time


input = sys.stdin.readline
n = int(input())
m_list = [[0]*n for _ in range(n)]
for _ in range(n):
    input_list = list(map(int, input().split()))
    index = input_list[0] - 1
    if input_list[1] > 0:
        for a in input_list[2:]:
            m_list[index][a-1] = 1
    
d_list = [0]*n
f_list = [0]*n
flag_list = [0]*n # 0: 未到達, 1: 処理中, 2: 完了
for i in range(n):
    if flag_list[i] == 0:
        dfs(i)

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

Python: G = {}
N = int(input())
for _ in range(N):
    L = list(map(int, input().split()))
    G[L[0]] = L[2:]

# print(G)
d = [-1] * N
f = [-1] * N
q = [1]
visited = [False] * N

time = 1


def dfs(v):
    global time
    visited[v-1] = True

    for nv in G[v]:
        if d[nv-1] < 0:
            d[nv-1] = time
            time += 1
        if not visited[nv-1]:
            dfs(nv)

    f[v-1] = time
    time += 1


for i in range(1, N+1):
    if not visited[i-1]:
        d[i-1] = time
        time += 1
        dfs(i)

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

Python: import math
import copy
import sys
import fractions
# import numpy as np
# import statistics
import decimal
import heapq
import collections
import itertools
import bisect


# from operator import mul

# sys.setrecursionlimit(100001)


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

# ===FUNCTION===

def getInputIntList():
    outputDataList = []
    inputData = input().split()
    outputDataList = [int(n) for n in inputData]

    return outputDataList


def getSomeInputInt(n):
    outputDataList = []
    for i in range(n):
        inputData = int(input())
        outputDataList.append(inputData)

    return outputDataList


def getSomeInputListInt(n):
    inputDataList = []
    outputDataList = []
    for i in range(n):
        inputData = input().split()
        inputDataList = [int(n) - 1 for n in inputData]
        outputDataList.append(inputDataList)

    return outputDataList


# ===CODE===

n = int(input())

data = getSomeInputListInt(n)

ans = [[] for _ in range(n)]

edge = []
for d in data:
    edge.append(d[2:])


def dfs(i, cnt):
    if len(ans[i]) > 0:
        return cnt

    cnt += 1

    ans[i].append(cnt)
    for j in range(len(edge[i])):
        cnt = dfs(edge[i][j], cnt)

    cnt += 1
    ans[i].append(cnt)

    return cnt

tmp = 0
for i in range(n):
    tmp = dfs(i, tmp)

for i in range(n):
    print(i + 1, *ans[i], sep=" ")

Python: class Node:
    def __init__(self, data):
        self.data = data
        self.neighbors = list()
        self.find_time = 0
        self.end_time = 0

N = int(input())
work_id = 0
nodes = list()
nodes.append(Node(0))


for _ in range(N):
    tmp_list = list( map(int, input().split()) )
    node = Node(tmp_list[0])
    for i in range(tmp_list[1]):
        node.neighbors.append(tmp_list[i+2])
    nodes.append(node)
    nodes[0].neighbors.append(node.data)

# for node in nodes:
#     print(node.data, ":", node.neighbors)


def search(node):
    global work_id

    if node.find_time != 0:
        return
    
    if node.data != 0:
        work_id += 1
        node.find_time = work_id

    if len(node.neighbors) > 0:
        for neighbor in node.neighbors:
            search(nodes[neighbor])
    
    if node.data != 0:
        work_id += 1
        node.end_time = work_id

search(nodes[0])

for node in nodes:
    if node.data == 0: continue
    print(node.data, node.find_time, node.end_time)