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()
}

C++: #include<iostream>
#include<stack>
using namespace std;
#define N 101
#define gray 1
#define white 0
#define black 2
int n,m[N][N];
int color[N],d[N],f[N],tt;
int nt[N];
int next(int u)
{
	for(int v=nt[u];v<n;v++)
	{
		nt[u]=v+1;
		if(m[u][v]) return v;
	}
	return -1;
}
void dfs_v(int u)
{
	for(int i=1;i<=n;i++)
	{
		nt[i]=0;
	}
	stack<int> s;
	s.push(u);
	d[u]=++tt;
	color[u]=gray;
	while(!s.empty())
	{
		int x=s.top();
		int v=next(x);
		if(v!=-1)
		{
			if(color[v]==white)
			{
				color[v]=gray;
				d[v]=++tt;
				s.push(v);
			}
		}else
			{
				s.pop();
				color[x]=black;
				f[x]=++tt;
			}
	}
}
void dfs()
{
	for(int i=1;i<=n;i++)
	{
		color[i]=white;
		nt[i]=0;
	}
	tt=0;
	for(int i=1;i<=n;i++)
	{
		if(color[i]==white)
		{
			dfs_v(i);
		}
	}
	for(int i=1;i<=n;i++)
	{
		printf("%d %d %d\n",i,d[i],f[i]);
	}
}
int main()
{
	int v,k,u;
	cin>>n;
	for(int i=1;i<=n;i++)
	{
		for(int j=1;j<=n;j++)
		{
			m[i][j]=0;
		}
	}
	for(int i=1;i<=n;i++)
	{
		cin>>u>>k;
		for(int j=1;j<=k;j++)
		{
			cin>>v;
			m[u][v]=1;
		}
	}
	dfs();
	return 0;
}

C++: #include <iostream>
using namespace std;

static const int N = 100;
static const int WHITE = 0;
static const int GRAY = 1;
static const int BLACK = 2;

int M[N][N] = {0}, color[N] = {0}, d[N], f[N], tt = 0, n;

void dfs_visit(int u) {
  int v;
  color[u] = GRAY;
  d[u] = ++tt;
  for (v = 0; v < n; v++) {
    if (M[u][v] == 0) continue;
    if (color[v] == WHITE) {
      dfs_visit(v);
    }
  }
  color[u] = BLACK;
  f[u] = ++tt;
}

int main(void) {
  int u, v, k, i, j;

  cin >> n;
  for (i = 0; i < n; i++) {
    cin >> u >> k;
    u--;
    for (j = 0; j < k; j++) {
      cin >> v;
      v--;
      M[u][v] = 1;
    }
  }
  dfs_visit(0);

  for (u = 0; u < n; u++) {
    cout << u + 1 << " " << d[u] << " " << f[u] << endl;
  }

  return 0;
}

C++: #include<bits/stdc++.h>
using namespace std;

#define White 0 //未訪問
#define Gray 1 //訪問中、または未訪問へのEdgeがある
#define Black 2 //訪問済み

int n;
int Graph[100][100] = {};

int color[100] = {}, d[100], f[100], tt; 
// d[v] = v 訪問時の時間 f[v] = v の隣接リスト調査後の時間 tt = 時間の記録

int nt[100] = {};


//u に隣接する v を番号順に取得
int next(int u){
  for(int v = nt[u] ; v < n ; v++ ){
    nt[u] = v + 1;
    if(Graph[u][v] != 0) return v;
  }
  return -1;
}

void dfs_visit(int r){
  stack<int> S;
  S.push(r); //スタート地点をスタックに積む

  color[r] = Gray; //スタート地点を訪問済みに

  tt++;
  d[r] = tt; //時間を取得

  while(!S.empty()){
    int u = S.top();  //topの値を入れる
    int v = next(u);
    if(v != -1){
      //末訪問なら訪問中にし時間を取得、次の頂点をスタックに積む
      //どちらでもなければ、popでスタックから外し訪問済みにする
      if(color[v] == White){ 
	color[v] = Gray;
	tt++;
	d[v] = tt;
	S.push(v);
      }
    }else{
      S.pop();
      color[u] = Black;
      tt++;
      f[u] = tt;
    }
  }
}
  
void dfs(){
  tt = 0;

  for(int u = 0 ; u < n ; u++){
    if(color[u] == White) dfs_visit(u); //その頂点が未訪問なら
  }

  for(int i = 0 ; i < n ; i++){
    cout << i + 1 << " " << d[i] << " " << f[i] << endl;
  }
}

int main(){
  int u, k, v; //u = 頂点番号 k = 出次数 v = u に隣接する頂点番号

  cin >> n;
     
  for(int i = 0 ; i < n ; i++){
    cin >> u >> k; 
    u--;
    for(int j = 0 ; j < k ; j++){
      cin >> v; 
      v--;
      Graph[u][v] = 1;
    }
  }

  dfs();
     
  return 0;
}