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
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)
		}
	}
	ans := make([][2]int, N)
	time := 0
	found := make(map[int]bool)
	var dfs func(cur int)
	dfs = func(cur int) {
		time++
		ans[cur][0] = time
		found[cur] = true
		for i := 0; i < len(G[cur]); i++ {
			next := G[cur][i]
			if !found[next] {
				dfs(G[cur][i])
			}
		}
		time++
		ans[cur][1] = time
	}
	for i := 0; i < N; i++ {
		if !found[i] {
			dfs(i)
		}
	}

	for i := 0; i < N; i++ {
		fmt.Fprint(wtr, i+1)
		for j := 0; j < 2; j++ {
			fmt.Fprint(wtr, " ")
			fmt.Fprint(wtr, ans[i][j])
		}
		fmt.Fprintln(wtr)
	}
	wtr.Flush()
}

Python: n = int(input())
graph = {}
ans = []
for i in range(n):
    t = list(map(int, input().split()))
    v = t[0]
    k = t[1]
    graph[v] = [t[i+2] for i in range(k)]
    ans.append([v,None,None])

class Time:
    def __init__(self):
        self.time = 0
    def getTime(self):
        self.time += 1
        return self.time

t = Time()

def dfs(graph, target):
    # ???????????????????¨????
    if ans[target - 1][1] is None:
        ans[target - 1][1] = t.getTime()
    if graph[target] == []:
        if ans[target - 1][2] is None:
            ans[target - 1][2] = t.getTime()        
        return
    for v in sorted(graph[target]):
        # # ???????????????????¨????        
        if ans[v - 1][1] is None:
            ans[v - 1][1] = t.getTime()        
        dfs(graph,v)
    if ans[target - 1][2] is None:
        ans[target - 1][2] = t.getTime()

dfs(graph, 1)
for row in ans:
    print(*row)

Python: def dfs(v):  # vを訪問する
    global time
    seen[v] = 1
    start[v] = time
    time += 1

    for next_v in graph[v]:
        if seen[next_v]: continue
        dfs(next_v)
    
    end[v] = time
    time += 1


n = int(input())
graph = []
for _ in range(n):
    line = list(map(int, input().split()))
    graph.append([v - 1 for v in line[2:]])

seen = [0] * n  # 0: 未訪問、1: 訪問済
start = [0] * n
end = [0] * n
time = 1

for v in range(n):
    if not seen[v]: dfs(v)

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

Python: n=int(input())
seen=[-1]*n
first_order=[0]*n
last_order=[0]*n
cnt=0
def dfs(G,s):
    global cnt
    first_order[s]=cnt+1
    cnt+=1
    seen[s]=1
    for nv in G[s]:
        if(seen[nv]!=-1):
            continue
        dfs(G,nv)
    last_order[s]=cnt+1
    cnt+=1

G=[[] for i in range(n)]
for i in range(n):
    li=list(map(int,input().split()))
    for x in range(2,len(li)):
        G[i].append(li[x]-1)
for i in range(n):
    if(seen[i]==-1):
        dfs(G,i)
for i in range(n):
    print(i+1,first_order[i],last_order[i])

Python: def d(u):
 global t
 C[u]=0;t+=1;D[u]=t
 for v in R:
  if M[u][v]and C[v]:d(v)
 t+=1;F[u]=t
N=int(input());R=range(N)
M=[[0]*N for _ in R]
for e in[input().split()for _ in R]:
 for v in e[2:]:M[int(e[0])-1][int(v)-1]=1
C,D,F=[1]*N,[0]*N,[0]*N
t=0
for i in R:
 if C[i]:d(i)
for i in R:print(i+1,D[i],F[i])

Python: # coding: utf-8
timestamp = 1

stack = []
indata = []
visit = []      #?¨?????¨????
visitTime = []  #?¨???????????¨??????¨
lastTimeStack = []      #?¨?????????????????¨??????¨


def inputdata():
    global      visit
    global      indata
    global      visitTime

    n = int(input().rstrip())

    for i in range(n):
        visit.append(True)
        visitTime.append([0, 0])

        lst = [int(i) for i in input().rstrip().split(" ")]
        k = lst[1]
        v = []
        for j in range(k):
            v.append(lst[2 + j] - 1)
        indata.append(v)

def procV(n):
    global lastTimeStack
    global timestamp
    global visit
    global stack

    if visit[n]:
        stack.append(n)
        lastTimeStack.append(n)
        visitTime[n][0] = timestamp
        timestamp += 1
        visit[n] = False
    else:
        if visitTime[n][1] == 0:
            visitTime[n][1] = timestamp
            timestamp += 1

"""
main
"""
inputdata()
stack.append(0)             #?????????????´????push??????

while True:
    if len(stack) == 0:
        isNotVisit = True
        n = 0
        for i in visit:
            if i:
                isNotVisit = False
                stack.append(n)
                break
            n += 1
        if isNotVisit:
            break

    n = stack.pop()         #??????????????????pop??????
    procV(n)                #pop????????????????????????????????????

    #???????????¢???
    for i in reversed(indata[n]):
        if visit[i]:
            hasNotChildAdd = False
            stack.append(i)

i = 1
for val in visitTime:
    li = [i, val[0], val[1]]
    print(' '.join(map(str, li)))
    i += 1

Python: j = 1

def dfs(graph, start, result, visited=None):
    global j
    if visited == None:
        visited = []
    visited.append(start)
    result[start][1]  = j
    for next in graph[start][2:]:
        if next in visited:
            continue
        j += 1
        dfs(graph, next, result, visited)
    else:
        j += 1
        result[start][2] = j

n = int(input())
g = [[]]
r = [[i,0,0] for i in range(n + 1)]
v = []

for i in range(n):
    g.append(list(map(int, input().split())))


for i in range(1, n + 1):
    if i in v:
        continue
    dfs(g,i,r,v)

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

Python: def dfs_recursive(u):
    global time
    color[u] = 'gray'
    arrive[u] = time
    time += 1
    for v in range(n):
        if adjMat[u][v] == 1 and color[v] == 'white':
            dfs_recursive(v)
    color[u] = 'black'
    finish[u] = time
    time += 1


n = int(input())

adjMat = [[0] * n for _ in range(n)]
color = ['white'] * n
arrive = [0] * n
finish = [0] * n
time = 1

for _ in range(n):
    adj = list(map(int, input().split()))
    i = adj[0]
    v = adj[2:]
    for j in v:
        adjMat[i - 1][j - 1] = 1

for root in range(n):
    if color[root] == 'white':
        dfs(root)


for i in range(n):
    out = ''
    out += '{} {} {}'.format(i + 1, arrive[i], finish[i])
    print(out)