Go: package main

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

func main() {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)
	sc.Scan()
	num, _ := strconv.Atoi(sc.Text())
	nodes := make(map[int]*node)

	for i := 0; i < num; i++ {
		sc.Scan()
		id, _ := strconv.Atoi(sc.Text())
		sc.Scan()
		nodeNum, _ := strconv.Atoi(sc.Text())
		n := node{id, make([]int, 0), 0, 0}
		for j := 0; j < nodeNum; j++ {
			sc.Scan()
			nid, _ := strconv.Atoi(sc.Text())
			n.nexts = append(n.nexts, nid)
		}
		nodes[id] = &n
	}

	s := Stack{}
	for i := 1; i < len(nodes)+1; i++ {
		if nodes[i].s != 0 {
			continue
		}
		walk(i, &nodes, s)
	}
	for i := 1; i < len(nodes)+1; i++ {
		fmt.Printf("%v %v %v\n", (*nodes[i]).id, (*nodes[i]).s, (*nodes[i]).e)
	}
}

var time int

func walk(nid int, nodes *map[int]*node, s Stack) {
	n := (*nodes)[nid]
	if n.s != 0 {
		return
	}
	time++
	n.s = time
	s.Push(n)
	for _, v := range n.nexts {
		walk(v, nodes, s)
	}
	time++
	n.e = time
}

type node struct {
	id    int
	nexts []int
	s     int
	e     int
}

// Stack is Stack
type Stack struct {
	stack []interface{}
}

// Push new value
func (stack *Stack) Push(val interface{}) {
	stack.stack = append(stack.stack, val)
}

// Pop new value
func (stack *Stack) Pop() interface{} {
	val := stack.stack[len(stack.stack)-1]
	stack.stack = stack.stack[0 : len(stack.stack)-1]
	return val
}

Python: n = int(input())
m = [[0 for j in range(n)] for i in range(n)]
color = [0 for i in range(n)]
d = [0 for i in range(n)]
f = [0 for i in range(n)]
time = [0]


def dfs(u):
    color[u] = 1
    time[0] += 1
    d[u] = time[0]
    for i in range(n):
        if m[u][i] == 1 and color[i] == 0:
            dfs(i)

    color[u] = 2
    time[0] += 1
    f[u] = time[0]


def main():
    for i in range(n):
        data = list(map(int, input().split()))
        for j in range(2, len(data)):
            m[data[0]-1][data[j]-1] = 1

    for i in range(n):
        if color[i] == 0:
            dfs(i)

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


if __name__ == '__main__':
    main()

Python: 
n = int(input())
g_list = {}
for _ in range(n):
    n1, num, *cl = map(int, input().split())
    g_list[n1] = cl


# 深さ優先探索: クラス使って書く？
class Graph():
    def __init__(self, g_list):
        self.time = 0
        self.nodes = {}
        self.d = {}
        self.f = {}
        self.g_list = g_list

    def dfs(self, node):
        self.time += 1
        self.d[node] = self.time
        for node_ in self.g_list[node]:
            if node_ not in self.d:
                self.dfs(node_)
        self.time += 1
        self.f[node] = self.time


g = Graph(g_list)
for i in range(1, n+1):
    if i not in g.d:
        g.dfs(i)

for g, f in zip(sorted(g.d.items()), sorted(g.f.items())):
    print(g[0], g[1], f[1])

Python: from sys import stdin

X = [ 0 for i in range(100) ]
d = [ 0 for i in range(100) ]
f = [ 0 for i in range(100) ]
G = [[ 0 for i in range(100) ] for i in range(100)]

t = 0

def DFS(i) :
	global t
	t += 1
	d[i] = t
	for j in range(n) :
		if G[i][j] != 0 and d[j] == 0 : DFS(j)
	t += 1
	f[i] = t


n = int(input())
for i in range(n) :
	X[i] = stdin.readline().strip().split()


for i in range(n) :
	for j in range(int(X[i][1])) :
		G[int(X[i][0])-1][int(X[i][j+2])-1] = 1

for i in range(n) :
	if d[i] == 0 : DFS(i)

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

Python: # -*- coding: utf_8 -*-

level = False
def debug(v):
    if level:
        print(v)

n = int(input())
a = [0]

for i in range(n):
    v = input().split()
    v.pop(0)
    v.pop(0)
    a.append([int(x) for x in v])

debug(a)
stack = [1]
results = [[0 for i in range(2)] for j in range(n + 1)]
results[0][0] = 0
time = 0

def depth_first_search(a, stack):
    debug(a)
    debug(results)
    debug(stack)
    global time
    if len(stack) == 0:
        return

    v = stack.pop()
    if results[v][0] == 0:
        time += 1
        results[v][0] = time

    es = a[v]
    if len(es) == 0 and results[v][1] == 0:
        time += 1
        results[v][1] = time

    if len(es) != 0:
        stack.append(v)
        next_vert = es.pop(0)
        if results[next_vert][0] == 0:
            stack.append(next_vert)

    depth_first_search(a, stack)

for i in range(n):
    stack = [i + 1]
    depth_first_search(a, stack)

debug(results)

results.pop(0)

i = 1
for row in results:
    print(str(i) + " " + str(row[0]) + " " + str(row[1]))
    i += 1

Python: n=int(input())
E=[0]*n
for _ in range(n):
    u,k,*V=map(int,input().split())
    E[u-1]=sorted(V)[::-1]
todo=[1]
seen=[0]*n
d=[0]*n
f=[0]*n
t=0
while 0 in f:
    if not todo:
        todo.append(seen.index(0)+1)    
    if seen[todo[-1]-1]==0:
        seen[todo[-1]-1]=1
        t+=1
        d[todo[-1]-1]=t
        for v in E[todo[-1]-1]:
            if d[v-1]==0:
                todo.append(v)
    elif f[todo[-1]-1]==0:
        t+=1
        f[todo.pop()-1]=t
    else:
        todo.pop()
for i in range(n):
    print(i+1,d[i],f[i])

Python: n = int(input())
G = [[] for _ in range(n)]
u1 = 0
for _ in range(n):
    u, k, *v = [int(i) for i in input().split()]
    G[u - 1] = v
    if k != 0 and u1 == 0:
        u1 = u

time = 1
u = u1
D = []
F = []
out = [[i+1, 0, 0] for i in range(n)]
T = []
while True:
    if u not in D:
        out[u - 1][1] = time
        D.append(u)
        T.append(u)
    if G[u - 1] == [] or G[u - 1][0] in F:
        time += 1
        out[T.pop() - 1][2] = time
        F.append(u)
        if T == []:
            if len(D) == n:
                break
            else:
                for ni in range(n):
                    if ni + 1 not in D:
                        u = ni + 1
                        break
        else:
            u = T[-1]
    else:
        u = G[u - 1].pop(0)
        time += 1

for ni in range(n):
    print(*out[ni])

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

# # 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
            

def get_next(u):
    for i in range(len(A[u])):
        if A[u][i] == 1 and d[i] == -1:
            return i
    return None

def dfs(u):
    global t
    s = []
    s.append(u)
    d[u] = t
    while len(s) > 0:
        p = s[-1]
        v = get_next(p)
        # print(p, 'next:', v)
        # t += 1
        # d[p] = t
        # print('poped:', p)
        
        if v is not None:
            
            if d[v] == -1:
                t += 1
                d[v] = t
                s.append(v)
                # print('[append:', v, 'at', t)
        else:
            t += 1
            # print('complete:', p, 'at', t)
            s.pop()
            f[p] = t


# def dfs(u):
#     s = []
#     t = 0
#     s.append(u)
    
#     while len(s) > 0:
#         p = s.pop()
#         print('init', str(p), d[p], t)
#         if d[p] > -1:
#             print('完了')
#             t += 1
#             f[p] = t
#         else:
#             t += 1
#             d[p] = t
#             print('---visit:', str(p), str(t), 'at', t)
#             has_node = False
#             for i in range(len(A[p])):
#                 if A[p][i] == 1 and d[i] == -1:
#                     print('reserve:', str(i))
#                     has_node = True
#                     s.append(i)
#                     break
#             if not has_node:
#                 t += 1
#                 f[p] = t
#         # print('H_complete:', str(p), str(t))
            


t = 0
for i in range(n):
    if d[i] == -1:
        t += 1
        # print('start from:', str(i))
        dfs(i)


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