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<bits/stdc++.h>

using namespace std;
#define WHITE 0 //未到達
#define GLAY 1 //訪問中
#define BLACK 2 //訪問完了
#define INF 1000000001

int num_node;

int dfs(const vector<vector<int> > &adj_list, vector<int> &d, vector<int> &f,const int id, int counter){
    counter++;
    d[id] = counter;
    if(id!=0){
        for(int i = 0; i < adj_list[id].size(); i++){
            if(d[adj_list[id][i]] == INF){
                counter = dfs(adj_list,d,f,adj_list[id][i],counter);
        }
        }   
    }
    else{
        for(int i = 1; i < num_node + 1;i++){
            if(d[i]==INF){
                counter = dfs(adj_list,d,f,i,counter);
            }
        }
    }
    
    counter++;
    f[id] = counter;
    return counter;
}



int main(){
    int id, k, to;
    cin >> num_node;
    vector<vector<int> > adj_list(num_node+1);
    vector<int> color[num_node+1];
    vector<int> d(num_node+1,INF), f(num_node+1,INF);

    adj_list[0].push_back(1);
    for(int j = 0 ;j < num_node;j++){
        cin >> id >> k;
        for(int i =0;i < k; i++){
            cin >> to;
            adj_list[id].push_back(to);
        }    
    }
    
    dfs(adj_list, d, f, 0, -1);
    for(int i=1;i <= num_node; i++){
        printf("%d %d %d\n",i,d[i],f[i]);
    }

    return 0;
}

C++: #include<iostream>
#include<vector>
using namespace std;
int n;
vector < int > G[105];
int st[105] = {};
int et[105];
int t = 1;

void dfs(int v)
{
    if (st[v] != 0) return;
    st[v] = t;
    t++;
    for (auto& x : G[v]) {
        dfs(x);
    }
    et[v] = t;
    t++;
}

int main()
{
    cin >> n;
    for (int i = 0; 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);
        }
    }
    for (int i = 1; i <= n; i++) dfs(i);
    for (int i = 1; i <= n; i++) {
        cout << i << " " << st[i] << " " << et[i] << endl;
    }
}

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

int n, t = 0;
int v[100][100];
int d[100], f[100], r[101];

void st(int id) {
	if (!r[id]) {
		r[id]++;
		d[id - 1] = ++t;
		for (int i = 0; i < n; i++)
			if (v[id - 1][i])
				st(i + 1);
		f[id - 1] = ++t;
	}
}

int main()
{
	cin >> n;

	for (int i = 0; i < n; i++) {
		int u, k, s;

		cin >> u >> k;

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

	for(int i = 0; i < n; i++)
		st(i);

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

	return 0;
}

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

#define WHITE 0
#define GRAY 1
#define BLACK 2

int G[101][101];
int color[101];
int n;
int d[101], f[101], t;

void search_loop(int i)
{
	int next;
	d[i] = ++t;
	color[i] = GRAY;
	cout << i << " " << t << endl;
	for(next = 1; next <= n; next++){
		if(G[i][next] > 0 && color[next] != BLACK){
			search_loop(next);
		}
	}
	f[i] = ++t;
	color[i] = BLACK;
	cout << i << " " << t << endl;
	return;
}

void dfs()
{
	int i;
	for(i = 1; i <= n; i++) color[i] = WHITE;  // initialize.

	t = 0;
	for(i = 1; i <= n; i++){
		if(color[i] == WHITE) search_loop(i);
	}
	for(i = 1; i <= n; i++){
		cout << i << " " << d[i] << " " << f[i] << endl;
	}
	return ;
}

int main()
{
	int i, j, k, e;
	cin >> n;
	for(i = 1; i <= n; i++){
		for(j = 1; j <= n; j++){
			G[i][j] = 0;
		}
	}
	do{
		cin >> i >> e;
		for(j = 1; j <= e; j++){
			cin >> k;
			G[i][k] = 1;
		}
	}while(i < n);

	dfs();

	return 0;
}

C++: #include <iostream>
#include <vector>

#define MAX 101

using namespace std;

int visited[MAX],d[MAX],f[MAX];
int tt=0;
vector<int> G[MAX];

void dfs(int u){
  d[u]=++tt;
  visited[u]=1;
  for(int i=0;i<G[u].size();i++){
    if(visited[G[u][i]]==0) dfs(G[u][i]);
  }
  f[u]=++tt;
}

int main(){
  int n; cin >> n;
  for(int i=1;i<=n;i++) visited[i]=0;
  for(int i=0;i<n;i++){
    int u,k; cin >> u >> k;
    for(int i=0;i<k;i++){
      int v; cin >> v;
      G[u].push_back(v);
    }
  }
  for(int i=1;i<=n;i++){
    if(visited[i]==0) dfs(i);
  }
  for(int i=1;i<=n;i++){
    cout << i << " " << d[i] << " " << f[i] << endl;
  }
}

C++: #include<iostream>
#include<vector>
#include<utility>
using namespace std;
vector<int> l[101];
int matrix[100][100];
pair<int,int> t[101];
bool visited[101];
int tim=0;
void dfs(int cur)
{
    tim+=1;
    t[cur].first=tim;
    //cerr<<"visiting "<<cur<<' '<<tim<<endl;
    visited[cur]=true;
    
    for(int i=0;i<l[cur].size();i++)
    {
        if((matrix[cur-1][l[cur][i]-1]==1)&&(visited[l[cur][i]]==false))
        {
            dfs(l[cur][i]);
        }
    }
    
    tim+=1;
    t[cur].second=tim;
    
    
}
int main()
{
    int n;
    cin>>n;
    for(int i=0;i<n;i++)
    {
        int u,k;
        cin>>u>>k;
        for(int j=0;j<k;j++)
        {
            int tmp;
            cin>>tmp;
            l[u].push_back(tmp);
        }
    }
    
    for(int i=0;i<n;i++)
    {
        for(int j=0;j<n;j++)
        {
            matrix[i][j]=0;
        }
    }
    
    visited[0]=false;
    for(int i=1;i<n+1;i++)
    {
        visited[i]=false;
        for(int j=0;j<l[i].size();j++)
        {
            matrix[i-1][l[i][j]-1]=1;
        }
    }
    
    for(int i=1;i<n+1;i++)
    {
        if(visited[i]==false)
            dfs(i);
    }
    
    for(int i=1;i<n+1;i++)
    {
        cout<<i<<" "<<t[i].first<<" "<<t[i].second<<endl;
    }
}