Go: package main

import (
	"bufio"
	"bytes"
	"fmt"
	"io"
	"os"
	"strconv"
	"strings"
)

const N = 100

const (
	WHITE = iota
	GRAY
	BLACK
)

type Graph struct {
	M               [N][N]int
	color, d, f, nt [N]int
	tt              int
}

func (g *Graph) next(u, n int) int {
	for v := g.nt[u]; v < n; v++ {
		g.nt[u] = v + 1
		if g.M[u][v] != 0 {
			return v
		}
	}
	return -1
}

func (g *Graph) dfsVisit(r, n int) {
	var S []int
	S = append([]int{r}, S...)
	g.color[r] = GRAY
	g.tt++
	g.d[r] = g.tt

	for len(S) != 0 {
		u := S[0]
		v := g.next(u, n)
		if v == -1 {
			S = S[1:]
			g.color[u] = BLACK
			g.tt++
			g.f[u] = g.tt
			continue
		}

		if g.color[v] != WHITE {
			continue
		}

		g.color[v] = GRAY
		g.tt++
		g.d[v] = g.tt
		S = append([]int{v}, S...)
	}
}

func (g *Graph) dfs(n int) string {
	for i := 0; i < n; i++ {
		g.color[i] = WHITE
	}
	g.tt = 0

	for u := 0; u < n; u++ {
		if g.color[u] == WHITE {
			g.dfsVisit(u, n)
		}
	}

	var out bytes.Buffer
	for i := 0; i < n; i++ {
		out.WriteString(fmt.Sprintf("%d %d %d\n", i+1, g.d[i], g.f[i]))
	}

	return strings.TrimRight(out.String(), "\n")
}

func answer(reader io.Reader) string {
	sc := bufio.NewScanner(reader)
	sc.Split(bufio.ScanWords)

	sc.Scan()
	n, _ := strconv.Atoi(sc.Text())

	var g Graph
	for i := 0; i < n; i++ {
		sc.Scan()
		u, _ := strconv.Atoi(sc.Text())
		sc.Scan()
		k, _ := strconv.Atoi(sc.Text())
		u--
		for j := 0; j < k; j++ {
			sc.Scan()
			v, _ := strconv.Atoi(sc.Text())
			v--
			g.M[u][v] = 1
		}
	}

	return g.dfs(n)
}

func main() {
	fmt.Println(answer(os.Stdin))
}

Python: #!/usr/bin/env python
from __future__ import division, print_function
from sys import stdin


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(stdin.readline())

    L = []
    for _ in xrange(num):
        L.append([int(s) for s in stdin.readline().split()[2:]])

    d = [0] * num
    f = [0] * num
    walk(0, 0, L, d, f)

    for i in xrange(num):
        print(i+1, d[i], f[i])


main()

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

Python: from collections import defaultdict

def dfs(here, connect, visited, answer):
    global time
    answer[here][1] = time
    time += 1
    visited[here] = 1
    for c in connect[here]:
        if not visited[c]:
            dfs(c, connect, visited, answer)
    answer[here][2] = time
    time += 1

v_num = int(input())
connect = defaultdict(list)
for _ in range(v_num):
    inp = [int(n) - 1 for n in input().split(" ")]
    connect[inp[0]].extend(sorted(inp[2:]))
answer = [[n + 1 for m in range(3)] for n in range(v_num)]
time = 1
visited = [0 for n in range(v_num)]
for i in range(v_num):
    if not visited[i]:
        dfs(i, connect, visited, answer)
for v in range(v_num):
    print(*answer[v])

Python: # coding=utf-8

n = int(input())
first_v = 0
time = 0
L = []
d = [None for _ in range(n)]
f = [None for _ in range(n)]
stuck = []
for _ in range(n):
    u, k, *v = map(int, input().split())
    L.append(list(map(lambda x: x-1, v)))

v = first_v #??¢?´¢????????????
while True:
    """print("------------------------------")
    print("stuck:", *stuck)
    print("L:", L)
    print("d:", *d)
    print("f:", *f)
    print("time:", time)
    print("v:", v)"""
    if len(L[v]) > 0:
        stuck.append(v)
        if not d[v]:
            time += 1
            d[v] = time
        v = L[v].pop(0)
    elif len(stuck) > 0:
        if not d[v]:
            time += 1
            d[v] = time
        if not f[v]:
            time += 1
            f[v] = time
        v = stuck.pop(-1)
    else:
        time += 1
        f[first_v] = time
        break

for i in range(n):
    print("{} {} {}".format(i+1, d[i], f[i]))

Python: # http://judge.u-aizu.ac.jp/onlinejudge/review.jsp?rid=4647653#1



import sys
sys.setrecursionlimit(10 ** 8)
input = sys.stdin.readline

class Graph:
    def __init__(self, n, dictated=False, decrement=True, edge=[]):
        self.n = n
        self.dictated = dictated
        self.decrement = decrement
        self.edge = [set() for _ in range(self.n)]
        self.parent = [-1]*self.n
        self.info = [-1]*self.n
        for x, y in edge:
            self.add_edge(x,y)

    def add_edge(self,x,y):
        if self.decrement:
            x -= 1
            y -= 1
        self.edge[x].add(y)
        if self.dictated == False:
            self.edge[y].add(x)

    def add_adjacent_list(self,i,adjacent_list):
        if self.decrement:
            self.edge[i] = set(map(lambda x:x-1, adjacent_list))
        else:
            self.edge[i] = set(adjacent_list)

    def path_detector(self, start=0, time=0):
        """
        :param p: スタート地点
        :return: 各点までの距離と何番目に発見したかを返す
        """

        edge2= []
        for i in range(self.n):
            edge2.append(sorted(self.edge[i], reverse=True))

        p, t = start, time
        self.parent[p] = -2
        full_path = [(p + self.decrement,t)]
        while True:
            if edge2[p]:
                q = edge2[p].pop()
                if q == self.parent[p] and not self.dictated:
                    """ 逆流した時の処理 """
                    """"""""""""""""""""
                    continue
                if self.parent[q] != -1:
                    """ サイクルで同一点を訪れた時の処理 """
                    """"""""""""""""""""
                    continue
                self.parent[q] = p
                p, t = q, t + 1
                full_path.append((p + self.decrement, t))
            else:
                """ 探索完了時の処理 """
                full_path.append((p + self.decrement, t))
                """"""""""""""""""""
                if p == start and t == time:
                    break
                p, t = self.parent[p], t-1
                """ 二度目に訪問時の処理 """
                """"""""""""""""""""
        return full_path

    def path_list(self):
        """
        :return: 探索経路を返す。
        """
        self.parent = [-1]*self.n
        res = []
        for p in range(self.n):
            if self.parent[p] == -1:
                res.append(self.path_detector(start=p, time=1))
        return res

    def draw(self):
        """
        :return: グラフを可視化
        """
        import matplotlib.pyplot as plt
        import networkx as nx

        if self.dictated:
            G = nx.DiGraph()
        else:
            G = nx.Graph()
        for x in range(self.n):
            for y in self.edge[x]:
                G.add_edge(x + self.decrement, y + self.decrement)
        nx.draw_networkx(G)
        plt.show()

def make_graph(dictated=False, decrement=True):
    """
    自己ループの無いグラフを生成。N>=2
    :param dictated: True = 有効グラフ
    :param decrement: True = 1-indexed
    :return:
    """
    import random
    N = random.randint(2, 5)
    if N > 2:
        M_max = (3*N-6)*(1+dictated)
    else:
        M_max = 1
    graph = Graph(N, dictated, decrement)
    for _ in range(random.randint(0,M_max)):
        graph.add_edge(*random.sample(range(decrement, N+decrement), 2))
    return graph

##################################################################
# 入力が隣接リストの場合
##################################################################

N = int(input())  # 頂点数

graph = Graph(N,dictated=True, decrement=True)

for i in range(N):  # [[頂点1と連結している頂点の集合], [頂点2と連結している頂点の集合],...]
    points = list(map(int, input().split()))[2:]
    graph.add_adjacent_list(i, points)


data = graph.path_list()

from itertools import chain
data = list(chain.from_iterable(data))

res = [[i+1,0,0] for i in range(N)]
for time, a in enumerate(data, start=1):
    i = a[0] - 1
    if res[i][1]:
        res[i][2] = time
    else:
        res[i][1] = time

for a in res:
    print(*a)