Go: package main

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

// I/O
type Scanner struct {
	sc *bufio.Scanner
}

func NewScanner() *Scanner {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)
	sc.Buffer(make([]byte, 1024), int(1e+9))
	return &Scanner{sc}
}

func (s *Scanner) nextStr() string {
	s.sc.Scan()
	return s.sc.Text()
}

func (s *Scanner) nextInt() int {
	i, e := strconv.Atoi(s.nextStr())
	if e != nil {
		panic(e)
	}
	return i
}

func (s *Scanner) nextFloat() float64 {
	f, e := strconv.ParseFloat(s.nextStr(), 64)
	if e != nil {
		panic(e)
	}
	return f
}

func (s *Scanner) nextRuneSlice() []rune {
	return []rune(s.nextStr())
}

func (s *Scanner) nextIntSlice(n int) []int {
	res := make([]int, n)
	for i := 0; i < n; i++ {
		res[i] = s.nextInt()
	}
	return res
}

func (s *Scanner) nextFloatSlice(n int) []float64 {
	res := make([]float64, n)
	for i := 0; i < n; i++ {
		res[i] = s.nextFloat()
	}
	return res
}

// Arithmetic
func max(nums ...int) int {
	m := nums[0]
	for _, i := range nums {
		if m < i {
			m = i
		}
	}
	return m
}

func min(nums ...int) int {
	m := nums[0]
	for _, i := range nums {
		if m > i {
			m = i
		}
	}
	return m
}

func abs(x int) int {
	if x > 0 {
		return x
	}
	return -x
}

func pow(x, y int) int {
	res := 1
	for i := 0; i < y; i++ {
		res *= x
	}
	return res
}

func ceil(a, b int) int {
	if a%b == 0 {
		return a / b
	} else {
		return a/b + 1
	}
}

// Sort
type RuneSlice []rune

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

// Main
func main() {
	sc := NewScanner()
	wtr := bufio.NewWriter(os.Stdout)
	N := sc.nextInt()
	G := make([][]int, N)
	for i := 0; i < N; i++ {
		u, k := sc.nextInt()-1, sc.nextInt()
		for j := 0; j < k; j++ {
			G[u] = append(G[u], sc.nextInt()-1)
		}
	}
	ans := make([][2]int, N)
	time := 0
	found := make(map[int]bool)
	var dfs func(cur int)
	dfs = func(cur int) {
		time++
		ans[cur][0] = time
		found[cur] = true
		for i := 0; i < len(G[cur]); i++ {
			next := G[cur][i]
			if !found[next] {
				dfs(G[cur][i])
			}
		}
		time++
		ans[cur][1] = time
	}
	for i := 0; i < N; i++ {
		if !found[i] {
			dfs(i)
		}
	}

	for i := 0; i < N; i++ {
		fmt.Fprint(wtr, i+1)
		for j := 0; j < 2; j++ {
			fmt.Fprint(wtr, " ")
			fmt.Fprint(wtr, ans[i][j])
		}
		fmt.Fprintln(wtr)
	}
	wtr.Flush()
}

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

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

using namespace std;


int adjacencyList[MAX + 1][MAX + 1];
int color[MAX + 1];
int d[MAX + 1];
int f[MAX + 1];
int n;
int timer;



int minWhiteNode(int v)
{

	for (int i = 1; i <= n; i++) {
		if (color[i] == WHITE && adjacencyList[v][i] == 1) {
			return i;
		}
	}
	return 	MAX + 1;
}


void dfs(int o)
{
	stack<int> S;
	int cr;


	S.push(o);
	color[o] = GRAY;
	d[o] = ++timer;

	while (S.size() > 0) 
	{
		cr = minWhiteNode(S.top());
		timer++;

		if (cr != MAX + 1) {
			S.push(cr);
			color[cr] = GRAY;
			d[cr] = timer;
		}
		else {
			int poped = S.top();
			S.pop();
			color[poped] = BLACK;
			f[poped] = timer;
		}
	}
}

int main(void)
{

	int u;
	int k;
	int v;


	cin >> n;

	for (int i = 0; i < n; i++) {
		cin >> u >> k;

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

	}

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

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

	return 0;
}

C++: #include<stdio.h>
int T=1,m[101][101],d[101]={0},a[101],b[101],n;
void visit(int u){
  int v; 
  a[u]=T++;
  d[u]=1;
  for(v=0;v<n;v++){
    if(m[u][v]==1&&d[v]==0){ 
      visit(v);
    }
  }   
  b[u]=T++;  
}
#include<stdio.h>
int main(){
  int k,i,j,u,v;
  scanf("%d",&n);
  for(i=0;i<n;i++)
    for(j=0;j<n;j++)
      m[i][j]=0;
 for(i=0;i<n;i++){
    scanf("%d%d",&u,&k);
    for(j=0;j<k;j++){
      scanf("%d",&v);
       m[u-1][v-1]=1;      
   }
 }
 visit(0);
 for(i=0;i<n;i++)
   printf("%d %d %d\n",i+1,a[i],b[i]);
 return 0;
}

C++: #define _CRT_SECURE_NO_WARNINGS
#define _USE_MATH_DEFINES
#include <iostream>
#include <cstdio>
#include <stack>
using namespace std;
stack<int> st;
int  v[102][101], n;
int  tim[102][2];
int ct = 1;
inline void search(int t) {
	if(!tim[t][0]) tim[t][0] = ct++;
	int tf = 0;
	for (int a = 1; a <= n; a++) {
		if (v[t][a]) {
			st.push(a);
			for (int i = 1; i <= n; i++) {
				v[i][a] = 0;
			}
			search(st.top());
			tf = 1;
		}
	}
		
	if(!tf) {
		st.pop();
		tim[t][1] = ct++;
		if(!st.empty()) search(st.top());
	}
}
int main() {
	st.push(1);
	int u, k, s;
	cin >> n;
	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++) {
		cin >> u;
		cin >> k;
		for (int j = 0; j < k; j++) {
			cin >> s;
			v[u][s] = 1;
		}
	}
	search(1);
	for (int i = 1; i <= n; i++) {
		cout << i << " " << tim[i][0] << " " << tim[i][1] << endl;
	}
	return 0;
}

C++: #include <iostream>

using namespace std;

const int N = 100;
int A[N][N] = {{0}};
int n;
int t = 0;
int d[N] = {0};
int f[N] = {0};

void dfs(int id) {
    // cerr << "begin: " <<  id << " " << t << endl;
    if (d[id] != 0) {
        return;
    }
    ++t;
    d[id] = t;

    for (int i = 0; i < n; ++i) {
        if (A[id][i] != 0) {
            dfs(i);
        }
    }

    // cerr << "end: " <<  id << " " << t << endl;
    if (f[id] == 0) {
        ++t;
        f[id] = t;
    }
}

int main() {
    cin >> n;
    for (int i = 0; i < n; ++i) {
        int u;
        cin >> u;

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

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


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

    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;
}