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))
}

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

int time1 = 0;
int a[110][110] = {};
int d[110] = {};
int f[110] = {};
int n;
int p;

void dfs(int cur){
  if(d[cur]==0){
    d[cur] = time1;
  }
  time1 += 1;

  for(int dst=1;dst<=n;dst++){
    if(a[cur][dst]==1&&d[dst]==0){
      dfs(dst);
      a[cur][dst]=2;
    }
  }
  f[cur] = time1;
  time1 += 1;
  for(int k=1;k<=n;k++){
    if(a[k][cur]==2){
      a[k][cur]=1;
      p+=1;
      dfs(k);
    }
  }
  if(p==0){
    for(int k=0;k<=n;k++){
      if(d[k]==0){
	dfs(k);
      }
    }
  }
}

int main(){
  cin>>n;
  for(int i=1;i<=n;i++){
    int u,k;
    cin>>u>>k;
    for(int j=0;j<k;j++){
      int v;
      cin>>v;
      a[i][v]=1;
    }
  }
  time1 += 1;
  dfs(1);
  for(int k=0;k<=n;k++){
    cout<<k<<" "<<d[k]<<" "<<f[k]<<endl;
  }
}

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

using namespace std;
int timetime = 0;

void dfs(int cur, vector<vector <int> > &list, vector<int> &d, vector<int> &f) {
		d[cur] =timetime;
		timetime +=1;
    for(int i = 0; i < list.size();i++){
      vector<int>::iterator n1end = list[cur].end();
	  vector<int>::iterator n1sres = find(list[cur].begin(),list[cur].end(),i);
      if(d[i] == -1 &&  n1end != n1sres  ){
        dfs(i,list,d,f);
      }
    }
    f[cur] = timetime;
    timetime +=1;
}

int main() {
  int np;
  int k,t,x;
  cin >> np ;
 
  vector <vector <int> > list(np);
  for(int i = 0;i<np;i++) {
    cin >> k;
    cin >> t;
    for(int j = 0; j < t ;j++) {
      cin >>x;
      list[k-1].push_back(x-1);
    }
  }
  for(int i = 0 ; i< np;i++){
	sort(list[i].begin(),list[i].end());
  }
  vector <int> d(np,-1);
  vector <int> f(np,0);
  dfs(0,list,d,f);
  	  int flag =0;
  do {
	  flag = 0;
	  for(int i = 0; i< np ;i++) {
		if(d[i] == -1){
				  dfs(i,list,d,f);
				  flag = 1;
				  break;
		}
	  }

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


  return 0;
}

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

int n;
int time_count = 0;
std::vector<std::pair<int, int>> times;
std::vector<std::vector<int>> vec;

void dfs(int id) {
    if (times[id-1].first == -1) {
        times[id-1].first = ++time_count; 
        for (int i = 1; i <= n; i++) {
            if (vec[id][i] == 1 && times[i-1].first == -1) {
                dfs(i);
            }
        }
        times[id-1].second = ++time_count;
    }
}

int main() {
    std::cin >> n;
    vec.assign(n+1, std::vector<int>(n+1, 0));
    for (int i = 0; i < n; i++) {
        times.push_back(std::make_pair(-1, -1));
    }
    for (int i = 0; i < n; i++) {
        int id, num, d;
        std::cin >> id >> num;
        for (int p = 0; p < num; p++) {
            std::cin >> d;
            vec[id][d] = 1;
        }
    }
    for (int i = 1; i <= n; i++) {
        dfs(i);
    }
    
    for (int i = 0; i < n; i++) {
        std::cout << i+1 << " " << times[i].first << " " << times[i].second << std::endl;
    }
}

C++: #include<iostream>
#include<vector>
#define NIL -1
using namespace std;

void DFS(int id, const vector<vector<int> >& a,
          vector<int>& find, vector<int>& finish){
    static int t = 1;
    if (find[id] != NIL) return;
    find[id] = t++;
    for (int i = 0; i < a[id].size(); i++) {
        DFS(a[id][i], a, find, finish);
    }
    finish[id] = t++;
}

int main(){
    int n;
    cin >> n;
    vector<vector<int> > a(n + 1);
    for (int i = 0; i < n; i++) {
        int u, k;
        cin >> u >> k;
        for (int j = 0; j < k; j++) {
            int v;
            cin >> v;
            a[u].push_back(v);
        }
    }
    vector<int> find(n + 1, NIL);
    vector<int> finish(n + 1, NIL);
    for (int i = 1; i <= n; i++) {
        DFS(i, a, find, finish);
    }
    for (int i = 1; i <= n; i++) {
        cout << i << " " << find[i] << " " << finish[i] << endl;
    }

    return 0;
}