Go: package main

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

// repr state of visited node
// WHITE yet visit
// GEAY  visiting
// BLACK visited
const (
	WHITE int = iota
	GRAY
	BLACK
)

type dfsGraph struct {
	g      [][]int
	colors []int
	stime  []int // Start time of visiting node
	ftime  []int // Finish time of visiting node
}

var time int

func makeAdjList() [][]int {
	var n int
	fmt.Scanf("%d", &n)

	adj := make([][]int, n)
	for i := 0; i < n; i++ {
		adj[i] = make([]int, n)
	}

	sc := bufio.NewScanner(os.Stdin)
	for i := 0; i < n; i++ {
		sc.Scan()
		nodeInfo := strings.Split(sc.Text(), " ")
		outDegree, _ := strconv.Atoi(nodeInfo[1])

		if outDegree > 0 {
			for k := 0; k < outDegree; k++ {
				j, _ := strconv.Atoi(nodeInfo[k+2])
				j-- // convert 1 based to 0 based
				adj[i][j] = 1
			}
		}
	}

	return adj
}

func (dg dfsGraph) dfsVisit(u int) {
	// 頂点uを訪問中に設定
	dg.colors[u] = GRAY
	time++
	dg.stime[u] = time

	// uの隣接nodeを訪問
	for v := 0; v < len(dg.g); v++ {
		if dg.g[u][v] == 0 {
			continue // 辺がなければスキップ
		}

		// vが未訪問なら訪問
		if dg.colors[v] == WHITE {
			dg.dfsVisit(v)
		}
	}

	// 頂点uを訪問済みに設定
	dg.colors[u] = BLACK
	time++
	dg.ftime[u] = time
}

func (dg dfsGraph) dfs() {
	for i := 0; i < len(dg.g); i++ {
		if dg.colors[i] == WHITE {
			dg.dfsVisit(i)
		}
	}
}

func (dg dfsGraph) printDfsTime() {
	for i := 0; i < len(dg.g); i++ {
		fmt.Printf("%d %d %d\n", i+1, dg.stime[i], dg.ftime[i])
	}
}

func main() {
	adj := makeAdjList()
	colors := make([]int, len(adj))
	stime := make([]int, len(adj))
	ftime := make([]int, len(adj))
	graph := dfsGraph{adj, colors, stime, ftime}
	graph.dfs()
	graph.printDfsTime()
}

Python: import heapq
from collections import deque
from enum import Enum
import sys
import math
from _heapq import heappush, heappop

BIG_NUM = 2000000000
MOD = 1000000007
EPS = 0.000000001

global current_time
global visited,go_time,back_time
global G


def dfs(node_id):
    global current_time #書かないとローカル変数扱いされる
    go_time[node_id] = current_time
    current_time += 1

    for next_node in G[node_id]:

        if visited[next_node] == True:
            continue
        visited[next_node] = True
        dfs(next_node)

    back_time[node_id] = current_time
    current_time += 1


V = int(input())

G = [[] for i in range(V)]

visited = [False]*V

go_time = [0]*V
back_time = [0]*V

for loop in range(V):
    node_id,num,*tmp_adj = list(map(int,input().split()))
    node_id -= 1
    for i in range(num):
        G[node_id].append(tmp_adj[i]-1)

current_time = 1;

for i in range(V):
    if visited[i] == True:
        continue
    visited[i] = True
    dfs(i)

for i in range(V):
    print("%d %d %d"%(i+1,go_time[i],back_time[i]))

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]))