Go: package main

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

type vertexId int

type vertex struct {
	id vertexId
	firstVisitAt int
	finishVisitAt int
	adjs []vertexId
}

func createVertex(id int, adjsInt []int) vertex {
	adjs := make([]vertexId, len(adjsInt))
	for i := 0; i < len(adjs); i++ {
		adjs[i] = vertexId(adjsInt[i])
	}
	return vertex{
		id: vertexId(id),
		firstVisitAt: 0,
		finishVisitAt: 0,
		adjs: adjs,
	}
}

func (v *vertex) doesAllAdjsVisited(vertices []vertex) bool {
	for _, vId := range v.adjs {
		adj := vertices[vId-1]
		if !adj.isVisited() {
			return false
		}
	}
	return true
}

func (v *vertex) isFirstVisit() bool {
	return v.firstVisitAt == 0
}

func (v *vertex) isVisited() bool {
	return v.firstVisitAt > 0
}

func (v *vertex) nextVertex(vertices []vertex) (vertexId, error) {
	for _, vId := range v.adjs {
		adj := vertices[vId-1]
		if !adj.isVisited() {
			return vId, nil
		}
	}
	return vertexId(-1), fmt.Errorf("illegal")
}

func dfs(currentId vertexId, timestamp int, vertices []vertex) int {
	timestamp = timestamp + 1
	currentVertex := &vertices[currentId-1]
	if currentVertex.isFirstVisit() {
		currentVertex.firstVisitAt = timestamp
	}
	for !currentVertex.doesAllAdjsVisited(vertices) {
		nextVertexId, _ := currentVertex.nextVertex(vertices)
		timestamp = dfs(nextVertexId, timestamp, vertices)
	}
	timestamp = timestamp + 1
	currentVertex.finishVisitAt = timestamp
	return timestamp
}

func main() {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)

	n, err := nextInt(sc)
	if err != nil {
		panic(err)
	}

	vertices := make([]vertex, n)
	for i := 0; i < n; i++ {
		id, err := nextInt(sc)
		if err != nil {
			panic(err)
		}
		adjN, err := nextInt(sc)
		if err != nil {
			panic(err)
		}
		adjs := make([]int, adjN)
		for j := 0; j < adjN; j++ {
			adjId, err := nextInt(sc)
			if err != nil {
				panic(err)
			}
			adjs[j] = adjId
		}
		vertices[i] = createVertex(id, adjs)
	}

	dfs(vertexId(1), 0, vertices)

	for i := 0; i < n; i++ {
		fmt.Printf("%d %d %d\n", vertices[i].id, vertices[i].firstVisitAt, vertices[i].finishVisitAt)
	}
}

func nextText(sc *bufio.Scanner) string {
	sc.Scan()
	return sc.Text()
}

func nextInt(sc *bufio.Scanner) (int, error) {
	return strconv.Atoi(nextText(sc))
}

C++: #include <iostream>
#include <stdio.h>
#include <cstring>
#include <math.h>
#include <algorithm>
#include <vector>
#include <string>
#include <stdlib.h>
#include <queue>
#include <stack>
#include <utility>
#define rep(i,n) for(int i=0;i<n;i++)
#define rrep(i,n) for(int i=n-1;i>=0;i--)
#define FOR(i,a,b) for(int i=a;i<b;i++)
#define ll long long
#define INF 1000000001
#define mod 1000000007
using namespace std;

int main(){
	int n;
	cin>>n;
	vector<vector<int> > v(n);
	vector<int> k(n);
	int x;
	rep(i,n){
		cin>>x;
		cin>>k[i];
		v[i].resize(k[i]);
		rep(j,k[i]){
			cin>>v[i][j];
			v[i][j]--;
		}
	}
	vector<int> a(n),b(n);
	stack<int> s;
	int count=1;
	s.push(0);
	a[0]=1;
	while(s.empty()==0){
		count++;
		int x=s.top();
		rep(i,k[x]){
			if(a[v[x][i]]==0){
				s.push(v[x][i]);
				a[v[x][i]]=count;
				break;
			}
			if(i==k[x]-1){
				k[x]=0;
			}
		}
		if(k[x]==0){
				b[x]=count;
				s.pop();
		}
		if(s.empty()==1){
			rep(i,n){
				if(a[i]==0){
					s.push(i);
					count++;
					a[i]=count;
					break;
				}
			}
		}
	}

	rep(i,n){
		cout<<i+1<<" "<<a[i]<<" "<<b[i]<<endl;;
	}

		



	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 n, m[N][N];
int color[N], d[N], f[N], tt;

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

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

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

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

    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();
}

C++: #include<iostream>
#include<stack>
using namespace std;
static const int N = 100;
static const int WHITE = 0;
static const int GRAY = 1;
static const int BLACK = 2;

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

int next(int u){
	for(int v = nt[u]; v < n; v++) {
		nt[u] = v + 1;
		if(M[u][v] == 1) 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 {
		   color[u] = BLACK;
		   S.pop();
		   f[u] = ++tt;
		}
	} 
}


void dfs() {
	for(int i = 0; i < n; i++) {
	     color[i] = WHITE;
	}
	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 n, k , u, 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 i = 0; i < k; i++) {
	        cin >> v;
	        v--;
		   M[u][v] = 1; 
     	}
	} 
	
	dfs();
	
	return 0;
}

C++: //ALDS1_11B
#include <iostream>
#include <vector>
#include <cstdio>
#define N 100
#define WHITE 0
#define GRAY 1
#define BLACK 2
using namespace std;

int n;
int color[N],d[N],f[N],tt;
vector< vector<int> > M(N,vector<int>(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;
}

void dfs(){
 int u;
 for(u=0;u<n;u++) color[u]=WHITE;
 tt=0;
 for(u=0;u<n;u++){
  if(color[u]==WHITE) dfs_visit(u);
 }
 for(u=0;u<n;u++){
  printf("%d %d %d\n",u+1,d[u],f[u]);
 }
}

int main(){
 int u,v,k,i,j;
 scanf("%d",&n);
 for(i=0;i<n;i++){
  scanf("%d %d",&u,&k);
  u--;
  for(j=0;j<k;j++){
   scanf("%d",&v);
   v--;
   M[u][v]=1;
  }
 }
 dfs();
 return 0;
}