Go: package main

import "fmt"

type node struct {
	id, d, v int
	adj      []node
}

var n int
var seen []bool
var graph []node

func max(a, b int) int {
	if a > b {
		return a
	}
	return b
}

func dfs(v, t int) int {
	// fmt.Printf("dfs(v %d, t %d) en:\n", v, t)
	seen[v] = true
	graph[v].v = t
	tt := t
	for _, vv := range graph[v].adj {
		if !seen[vv.id] {
			tt = max(tt, dfs(vv.id, tt+1))
		}
	}
	graph[v].d = tt + 1
	// fmt.Printf("dfs(v %d, t %d) ex: d %d\n", v, t, graph[v].d)
	return graph[v].d
}

func main() {
	fmt.Scan(&n)
	graph = make([]node, n+1)
	for i := 1; i <= n; i++ {
		var u, k, v int
		fmt.Scan(&u, &k)
		graph[u].id = u
		// 頂点uはk個の隣接頂点を持っている
		for j := 0; j < k; j++ {
			fmt.Scan(&v)
			var t node
			t.id = v
			graph[u].adj = append(graph[u].adj, t)
		}
	}
	// fmt.Println("n", n, "graph", graph)
	seen = make([]bool, n+1)
	// t := dfs(1, 1)
	v, t := 1, 1
	done := false
	for !done {
		tt := dfs(v, t)
		done = true
		for i := range seen {
			if !seen[i] {
				done = false
				v = graph[i].id
				t = tt
				break
			}
		}
	}
	for i := 1; i <= n; i++ {
		fmt.Printf("%d %d %d\n", i, graph[i].v, graph[i].d)
	}
}

Python: # -*- coding: utf-8 -*-
N = int(input())
adj = [[0]*N for _ in range(N)]
searched = {n: 0 for n in range(N)}
edge = {}

def find_all(list_, x, j=-1):
    return [i for i, n in enumerate(list_) if n==1 and n != j]


for n in range(N):
    inp = list(map(int, input().split()))
    edge[n] = inp[1]
    for i in inp[2:]:
        adj[inp[0]-1][i-1] = 1

time = 1
stack = []
unsearch = set(range(N))
uncomplete = set(range(N))
result = {n:{"found": 0, "finish": 0} for n in range(N)}

while len(unsearch) > 0 or len(stack) > 0:
    if len(stack) == 0:
        i = min(unsearch)
        result[i]["found"] = time
        unsearch.remove(i)
        time += 1

    
    while True:
        j = i
        for n in sorted(unsearch):
            if adj[i][n] == 1:
                j = n
                result[n]["found"] = time
                unsearch.remove(n)
                stack.append(i)
                time += 1
                break

        if i == j:
            result[i]["finish"] = time
    
            if len(stack) != 0:                
                i = stack.pop()
                time += 1
            else:
                break
        else:
            i = j
                
for n in range(N):
    print("{} {} {}".format(n, result[n]["found"], result[n]["finish"]))

Python: n = int(input())
g = [None] * n
visited = [0] * n
root = set(range(n))
ts = [[0, 0] for _ in range(n)]
t = 1

while n:
    l = list(map(int, input().split()))
    connected = [i - 1 for i in l[2:]]
    g[l[0] - 1] = [i - 1 for i in l[2:]]
    root -= set(connected)
    n -= 1


def dfs(i):
    global g, t, ts, visited
    lts = ts[i]
    lts[0] = t
    visited[i] = 1
    for c in g[i]:
        if not visited[c]:
            t += 1
            dfs(c)
    t += 1
    lts[1] = t


for r in sorted(root):
    dfs(r)

for i, v in enumerate(ts):
    print(i + 1, *v)

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:
		#print("break")
		break

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

Python: #!/usr/bin/env python
# -*- coding:utf-8 -*-
from __future__ import division,print_function
import time
import sys
import io
import re
import math
start = time.clock()
i = 0
def walk(index,tm,L,d,f):
    tm+=1
    d[index]=tm
    for i in L[index]:
        if not d[i-1]:
            tm=walk(i-1,tm,L,d,f)
    tm+=1
    f[index]=tm
    return tm
 
def main():
    num=int(sys.stdin.readline())
    L=[]
    for _ in range(num):
        L.append([int(s) for s in sys.stdin.readline().split()[2:]])
    d=[0]*num
    f=[0]*num
    tm=0
    for i in range(num):
        if not d[i]:
            tm=walk(i,tm,L,d,f)
    for i in range(num):
        print(i+1,d[i],f[i])
 
main()

Python: n = int(input())
A = [[0 for i in range(n)] for j in range(n)]

for i in range(n):
    u, k, *v = list(map(int, input().split()))
    for j in v:
        A[int(u)-1][int(j)-1] = 1
        A[int(j)-1][int(u)-1] = 1

# for row in A:
#     msg = ' '.join(map(str, row))
#     # print(msg)

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

t = 0
d[0] = t

# recursive


def dfs(u):
    global t
    # print('visit:', str(u), str(t))
    t += 1
    d[u] = t
    for i in range(len(A[u])):
        if A[u][i] == 1 and d[i] == -1:
            dfs(i)
    t += 1
    f[u] = t
            

dfs(0)


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

Python: n = int(input())
E = [[]]*n

for i in range(n):
    inputs = list(map(int, input().split()))
    if inputs[1]==0:
        continue
    else:
        for j in inputs[2:]:
            E[i] = E[i] + [j-1]

beg = [-1]*n
fin = [-1]*n  

t = 0      
def f(i):
    global t
    #print(i,t)
    t += 1
    beg[i] = t
    for c in E[i]:
        if beg[c]>0:
            continue
        else:
            f(c)
    t+=1
    fin[i] = t
    

for i in range(n):
    if beg[i]<0:
        f(i)
for i in range(n):
    print(i+1, beg[i], fin[i])

Python: # N=4
# G=[[2],[4],[],[3]]
import sys
sys.setrecursionlimit(1000000)

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

v=[False]*N
d=[0]*N
f=[0]*N
timecount=1

def dfs(i):
    global timecount
    if v[i] : return
    v[i] = True
    d[i] = timecount
    # print("D",i+1,timecount)
    timecount += 1
    for p in G[i]:
        dfs(p-1)
    # print("F",i+1,timecount)
    f[i] = timecount
    timecount += 1
    return

for i in range(N):
  if v[i]==0: dfs(i)

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

Python: class Node(object):
    def __init__(self, V):
        self.V = V
        self.find_time = 0
        self.finish_time = 0
        self.is_finded = False
 
 
n = int(input())
nodes = [0] * 101
for i in range(n):
    data = input().split()
    V = list(map(int, data[2:]))
    V.sort(reverse = True)
    nodes[int(data[0])] = Node(V)
 
find_q = []
find_q.append(1)
cnt = 1
q_size = len(find_q)
while q_size != 0:
    #print(find_q)
    node = nodes[find_q[q_size -1]]
 
    if node.is_finded == False:
        node.find_time = cnt
        cnt += 1
        node.is_finded = True
        if len(node.V) == 0:
            node.finish_time = cnt
            cnt += 1
            find_q.pop()
            q_size = len(find_q)
        else:
            for x in node.V:
                if x in find_q:
                    find_q.remove(x)
                if nodes[x].finish_time == 0: 
                    find_q.append(x)
            q_size = len(find_q)
 
    else:   #node is finded
        node.finish_time = cnt
        cnt += 1
        find_q.pop()
        q_size = len(find_q)
        continue
 
for i in range(1, n+1):
    if not isinstance(nodes[i], int):
        print(i, nodes[i].find_time, nodes[i].finish_time)