Go: package main

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

func getScanner(fp *os.File) *bufio.Scanner {
	scanner := bufio.NewScanner(fp)
	scanner.Split(bufio.ScanWords)
	scanner.Buffer(make([]byte, 1000005), 1000005)
	return scanner
}

func getNextString(scanner *bufio.Scanner) string {
	scanner.Scan()
	return scanner.Text()
}

func getNextInt(scanner *bufio.Scanner) int {
	i, _ := strconv.Atoi(getNextString(scanner))
	return i
}

func getNextInt64(scanner *bufio.Scanner) int64 {
	i, _ := strconv.ParseInt(getNextString(scanner), 10, 64)
	return i
}

func getNextUint64(scanner *bufio.Scanner) uint64 {
	i, _ := strconv.ParseUint(getNextString(scanner), 10, 64)
	return i
}

func getNextFloat64(scanner *bufio.Scanner) float64 {
	i, _ := strconv.ParseFloat(getNextString(scanner), 64)
	return i
}

func main() {
	fp := os.Stdin
	wfp := os.Stdout
	cnt := 0

	if os.Getenv("MASPY") == "ますピ" {
		fp, _ = os.Open(os.Getenv("BEET_THE_HARMONY_OF_PERFECT"))
		cnt = 1
	}
	if os.Getenv("MASPYPY") == "ますピッピ" {
		wfp, _ = os.Create(os.Getenv("NGTKANA_IS_GENIUS10"))
	}

	scanner := getScanner(fp)
	writer := bufio.NewWriter(wfp)
	solve(scanner, writer)
	for i := 0; i < cnt; i++ {
		fmt.Fprintln(writer, "-----------------------------------")
		solve(scanner, writer)
	}
	writer.Flush()
}

func solve(scanner *bufio.Scanner, writer *bufio.Writer) {
	n := getNextInt(scanner)
	g := graph{}
	g.ee = make([]Edges, n)
	g.visited = make([]bool, n)
	g.found = make([]int, n)
	g.leave = make([]int, n)
	for i := 0; i < n; i++ {
		u := getNextInt(scanner) - 1
		k := getNextInt(scanner)
		for j := 0; j < k; j++ {
			v := getNextInt(scanner) - 1
			g.ee[u] = append(g.ee[u], Edge{
				to: v,
				id: u,
			})
		}
	}
	for i := 0; i < n; i++ {
		sort.Sort(g.ee[i])
	}
	for i := 0; i < n; i++ {
		if g.visited[i] {
			continue
		}
		g.dfs(i)
	}

	for i := 0; i < n; i++ {
		fmt.Fprintln(writer, fmt.Sprintf("%d %d %d", i+1, g.found[i], g.leave[i]))
	}
}

// Edge ...
type Edge struct {
	to, id int
}

type Edges []Edge

func (a Edges) Len() int           { return len(a) }
func (a Edges) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }
func (a Edges) Less(i, j int) bool { return a[i].id < a[j].id }

type graph struct {
	ee           []Edges
	t            int
	n            int
	visited      []bool
	found, leave []int
}

func (g *graph) dfs(i int) {
	g.visited[i] = true
	g.t++
	g.found[i] = g.t
	for _, e := range g.ee[i] {
		if g.visited[e.to] {
			continue
		}
		g.dfs(e.to)
	}
	g.t++
	g.leave[i] = g.t
}

C++: #include<iostream>
#include<vector>
using namespace std;
int cnt=1;
void depth(vector< vector<int> > &vv,vector<int> &f,vector<int> &c,int num){
	f[num]=cnt;
	cnt++;
	for(int i=0; i<vv[num].size(); i++){
		if(vv[num][i]!=0 && f[i]==0){
			depth(vv,f,c,i);
		}
	}
	if(c[num]==0){
		c[num]=cnt;
		cnt++;
	}
}
int main(){
	int n;
	cin>>n;
	vector< vector<int> > v(n,vector<int> (n,0));
	vector<int> ft(n,0);
	vector<int> ct(n,0);
	int u[n];
	for(int i=0; i<n; i++){
		int k;
		cin>>u[i]>>k;
		for(int j=0; j<k; j++){
			int x;
			cin>>x;
			v[i][x-1]=1;
		}
	}
	for(int i=0; i<n; i++){
		if(ft[i]==0){
			depth(v,ft,ct,i);
		}
	}
	for(int i=0; i<n; i++){
		cout<<u[i]<<" "<<ft[i]<<" "<<ct[i]<<endl;
	}
  return 0;
}

C++:  #include<stdio.h>
#define Gray 0
#define White 1
#define Black 2
int time;
int d[101],f[101],color[101],Adj[101][101];  
int n;

void DFS_Visit(int u){
  int i;  
  color[u]=Gray;
  d[u]=++time;
  for(i=1;i<=n;i++){
    if(color[i]==White && Adj[u][i]==1) DFS_Visit(i);
  }
  color[u]=Black;
  f[u]=++time;
}

void DFS(){
  int i;
  for(i=1;i<=n;i++){
    color[i]=White;
  }
  time=0;
  for(i=1;i<=n;i++){
    if(color[i]==White) DFS_Visit(i);
}
}

main(){
  
  int k,i,j,t,g;

  scanf("%d",&n);
    for(i=0;i<=n;i++){
      for(j=0;j<=n;j++){
	Adj[i][j]=0;
      }
    } 
    
    for(i=1;i<=n;i++){
      scanf("%d",&g);    
      scanf("%d",&k);
      for(j=1;j<=k;j++){
	scanf("%d",&t);
	Adj[g][t]=1;   
      }
    } DFS();
    
    for(i=1;i<=n;i++){
   
      printf("%d %d %d\n",i,d[i],f[i]);
    }
    return 0;
}

C++: #include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
using Graph = vector<vector<int>>;

vector<bool> seen;
vector<int> first_order; // 行きがけ順
vector<int> last_order; // 帰りがけ順
void dfs(const vector<vector<int>> &G,int v,int& ptr){
  first_order[v] = ptr++;

  // vを訪問済みにする
  seen[v] = true;

  // vから行ける各頂点next_vについて
  for(auto next_v:G[v]){
    if(seen[next_v]) continue;
    dfs(G,next_v,ptr);
  }

  last_order[v] = ptr++;
}

int main(){
  //頂点数
  int n;
  cin >> n;

  Graph G(n+1);
  //頂点番号、隣接頂点数、隣接頂点番号
  for(int i=1;i<=n;i++){
    int u,k;
    cin >> u >> k;
    for(int j=0;j<k;j++){
      int v;
      cin >> v;
      G[u].push_back(v);
    }
  }

  seen.assign(n+1,false);
  first_order.resize(n+1);
  last_order.resize(n+1);
  int ptr = 1;
  for(int i=1;i<=n;i++){
    if(seen[i]) continue;
    dfs(G,i,ptr);
  }

  // 各頂点vの行きがけ順、帰りがけ順を出力
  for(int v = 1;v<=n;v++){
    cout << v << " " << first_order[v] << " " << last_order[v] << endl;
  }
}

C++: #include <iostream>
#include <stack>
using namespace std;
static const int N = 100;
static const int WHITE = 0;
static const int GREY = 1;
static const int 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_visit(int r) {
	for (int i = 0; i < n; i++) nt[i] = 0;

	stack<int> S;
	S.push(r);
	color[r] = GREY;
	d[r] = ++tt;

	while (!S.empty()) {
		int u = S.top();
		int v = next(u);
		if (v != -1) {
			if (color[v] == WHITE) {
				color[v] = GREY;
				d[v] = ++tt;
				S.push(v);
			}
		}
		else {
			S.pop();
			color[u] = BLACK;
			f[u] = ++tt;
		}
	}
}


void dfs() {
	for (int i = 0; i < n; i++) {
		color[i] = WHITE;
		nt[i] = 0;
	}
	tt = 0;

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


int main() {
	int u, k, v;

	cin >> n;
	for (int i = 0; i < n; i++) {
		for (int j = 0; j < n; j++) M[i][j] = 0;
	}

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

	dfs();

	return 0;
}