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 n, t;
int v[100][100];
int d[100], f[100];

void stamp(int id) {
	if (d[id - 1] == 0) {
		d[id - 1] = t;
		t++;
		int i = 0;
		while (v[id - 1][i] == 0)
			i++;
		if (i < n && d[i] == 0)
			stamp(i + 1);
		else
			stamp(id);
	}
	else if (f[id - 1] == 0) {
		int i;
		for(i = 0; i < n; i++)
			if (v[id - 1][i] == 1 && d[i] == 0)
				stamp(i + 1);
		if (i > n - 1 && f[id - 1] == 0) {
			f[id - 1] = t;
			t++;
			int j;
			for (j = n - 1; j > -1; j--)
				if (v[j][id - 1] == 1 && f[j] == 0 && d[j] == id - 1)
					stamp(j + 1);
			int k = 0;
			while (d[k] != 0)
				k++;
			if (k < n)
				stamp(k + 1);
		}
	}
	else	
		return;
}

int main()
{
	cin >> n;

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

	for (int i = 0; i < n; i++)
		for (int j = 0; j < n; j++)
			v[i][j] = 0;

	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;
		}
	}

	t = 1;
	stamp(1);

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

	return 0;
}

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

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], color[N], nxtNei[N];
int t, t1[N], t2[N];

int nxt(int u){
	for (int v = nxtNei[u]; v < n; ++v) {
		nxtNei[u] = v + 1;
		if (color[v] == WHITE && m[u][v] == 1) {
			return v;
		}
	}
	return -1;
}

void dfs(int r){
	for (int i = 0; i < n; ++i) nxtNei[i] = 0;
	stack<int> s;
	color[r] = GREY;
	s.push(r);
	t1[r] = t++;
	while (!s.empty()) {
		int u = s.top();
		int v = nxt(u);
		if (-1 == v){
			color[u] = BLACK;
			s.pop();
			t2[u] = t++;
			continue;
		}

		color[v] = GREY;
		s.push(v);
		t1[v] = t++;
	}
}

void search(){
	t = 1;
	for (int i = 0; i < n; ++i){
		color[i] = WHITE;
		nxtNei[i] = 0;
	}
	for (int i = 0; i < n; ++i) {
		if (color[i] == WHITE) dfs(i);
	}
	for (int i = 0; i < n; ++i){
		cout << i + 1 << " " << t1[i] << " " << t2[i] << endl;
	}
}


int main()
{
	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) {
		int u, d; cin >> u >> d;
		for (int j = 0; j < d; ++j) {
			int v; cin >> v;
			m[u - 1][v - 1] = 1;
		}
	}

	search();

	return 0;
}

C++: #include <utility>
#include <math.h>
#include <vector>
#include <algorithm>
#include <string>
#include <iostream>

using namespace std;

int c;
int a[100][100];
int times = 0;
vector<pair<int,int> > v;

vector<int> search(int node)
{
    vector<int> r;
    for(int i = 0;i<c;i++)
    {
        if(a[node][i] == 1)
            r.push_back(i);
    }
    return r;
}

int deep(int node)
{
    if(v[node].first == 0)
    {
        v[node].first = ++times;
        vector<int> r = search(node);
        for(int i = 0;i<r.size();i++)
        {
            deep(r[i]);
            
        }
        v[node].second = ++times;
    }
    else
        return -1;

    return 1;
}

int main() {

    cin >> c;
    for(int i= 0;i<c;i++)
        for(int j = 0;j<c;j++)
            a[i][j] = 0;
    v = vector<pair<int,int> >(c,{0,0});
    for(int i = 0; i<c;i++)
    {
        int rem[2];
        cin >> rem[0] >> rem[1];
        for(int j = 0;j<rem[1];j++)
        {
            int rem11;
            cin >> rem11;
            a[i][rem11-1] = 1;
        }
    }//cin fin
    for(int i = 0;i<c;i++)
    {
        if(v[i].first == 0)
            deep(i);
    }
    
    for(int i = 0; i<c;i++)
    {
        cout << i+1 << " " << v[i].first << " " << v[i].second << endl;
    }
    
    return 0;
}

C++: #include <iostream>
#include <stack>
#include <cstdio>

#define MAX 100
#define WHITE 0
#define GRAY 1
#define BLACK 2
#define NIL -1

using namespace std;

int adj[MAX+1][MAX+1];
int color[MAX+1],d[MAX+1],f[MAX+1];
stack<int> S;
int n;
int t=0;

int next(int u){
  for(int i=1;i<=n;i++){
    if(adj[u][i]==1&&color[i]==WHITE) return i;
  }
  return NIL;
}

void dfs(int u){
  S.push(u);
  color[u]=GRAY;
  d[u]=++t;
  while(S.empty()==false){
    u=S.top();
    int v=next(u);
    if(v!=NIL){
      color[v]=GRAY;
      d[v]=++t;
      S.push(v);
    }else{
      S.pop();
      color[u]=BLACK;
      f[u]=++t;
    }
  }
}

void dfs_init(){
  for(int i=1;i<=n;i++) color[i]=WHITE;
  dfs(1);
}

int main(){
  cin >> n;
  for(int i=1;i<=n;i++){
    int u,k; cin >> u >> k;
    for(int i=1;i<=n;i++) adj[u][i]=0;
    for(int i=0;i<k;i++){
      int v; cin >> v;
      adj[u][v]=1;
    }
  }
  dfs_init();
  for(int id=1;id<=n;id++){
    printf("%d %d %d\n",id,d[id],f[id]);
  }
}

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

const int Max = 100;
const int white = 0;
const int gray = 1;
const int black = 2;

int n, M[Max][Max];
int color[Max], d[Max], f[Max], tt;
int nt[Max];

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] = gray;
    d[r] = ++tt;

    while( !S.empty() ){
        int u = S.top();
        int v = next(u);
        if( v != -1){
            if(color[v] == white){
                color[v] = gray;
                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=00; 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;

}