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 <vector>
#include <algorithm>
using namespace std;

int n;
vector< vector<int> > do_thi; 
bool *da_duyet;
int *d;
int *f;
int timestamp;

void dfs(int dinh_dang_duyet) { 
	d[dinh_dang_duyet] = timestamp++; // Danh dau so buoc bat dau duyet dinh
	da_duyet[dinh_dang_duyet] = true; // Danh dau dinh da duoc duyet
	// Tim nhung dinh lan can
	for (int i = 0, lan_can = 0; i < do_thi[dinh_dang_duyet].size(); ++i) {
		lan_can = do_thi[dinh_dang_duyet][i];
		if (da_duyet[lan_can]) continue;
		dfs(lan_can);
	}
	f[dinh_dang_duyet] = timestamp++; // Danh dau so buoc khi ket thuc viec duyet dinh do
}

int main() {
	cin >> n; // Sau khi co gia tri n cu the moi cap phat kich thuoc o nho cho cac mang
	da_duyet = new bool[n + 1]; // Cap phat mang danh dau dinh da duyet hay chua (vi mang chi so tinh tu 0)
	d = new int[n + 1]; // Cap phat mang de luu thoi diem tim ra cac dinh
	f = new int[n + 1]; // Cap phat mang de luu thoi diem duyet xong cac dinh
	
	for (int i = 0; i <= n; ++i) { // Khoi tao cac gia tri cho moi dinh
		do_thi.push_back(vector<int>()); // Khoi tao vector cho moi dinh
		da_duyet[i] = false; // Khoi tao trang thai da duyet hay chua cho moi dinh
		d[i] = 0; // Khoi tao thoi diem tim ra moi dinh
		f[i] = 0; // Khoi tao thoi diem duyet xong moi dinh
	}
	for (int i = 0, k = 0, u = 0, v = 0; i < n; ++i) { // Xay dung cac canh cua do thi
		cin >> u; // Doc vao ID cua dinh u
		cin >> k; // Doc vao so dinh ke voi u (bac cua dinh u)

		for (int j = 0; j < k; ++j) { // Doc vao cac dinh lan can cua u, dua vao do thi
			cin >> v; // Doc vao moi dinh lan can
			do_thi[u].push_back(v); // Dua vao vector bieu dien tinh tuong ung
		}
	}
	
//	for (int i = 1; i <= n; ++i) { // Sap xep lai cac dinh lan can cua dinh i
//		sort(do_thi[i].begin(), do_thi[i].end());
//	}
	
	timestamp = 1;
	
	for (int i = 1; i <= n; ++i) { // Duyet tat ca cac dinh cua do thi
		if (da_duyet[i]) continue; // Neu dinh da duyet thi kiem tra tiep
		dfs(i);	// Neu dinh chua duyet thi dua vao ham dfs
	}
	
	for (int i = 1; i <= n; ++i) { // In ra ket qua
		cout << i << " " << d[i] << " " << f[i] << endl;
	}
	return 0;
}

C++: #include <bits/stdc++.h>

using namespace std;
int t;

void dfs(vector<vector<bool> >& A, vector<vector<int> >& B, int s, int n){
    for(int i = 0; i < n; i++){
        if(i == 0){
            if(B[s][1] == 0){
                B[s][1] = t;
                t++;
            }
        }
        if(A[s][i] == true){
            A[s][i] = false;
            dfs(A, B, i, n);
        }
        if(i == n-1){
            if(B[s][2] == 0){
                B[s][2] = t;
                t++;
            }
        }
    }
}

int main(void){

    //??£??\??????????????£??\???????????????
    int n, k;

    cin >> n;
    vector<vector<bool> > A(n, vector<bool>(n, false));
    for(int i = 0; i < n; i++){
        cin >> k >> k;
        for(int j = 0; j < k; j++){
            int input;
            cin >> input;
            A[i][input-1] = true;
        }
    }

   

    vector<vector<int> > B(n, vector<int>(3, false));
    for(int i = 0; i < n; i++){
        B[i][0] = i + 1;
    }

    t = 1;
    for(int k = 0; k < n; k++){
        if(B[k][1] == 0) dfs(A, B, k, n);
    }
    

    //??????
    for(int i = 0; i < n; i++){
        for(int j = 0; j < 3; j++){
            if(j != n-1) cout << B[i][j] << " ";
            else cout << A[i][j];
        }
        cout << endl;
    }
    return 0;
}

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 = n - 1; i > -1; i--)
			if (v[id - 1][i] == 1 && d[i] == 0)
				stamp(i + 1);
		if (i < 0 && 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] != 0)
					stamp(j + 1);
			if (j < 0) {
				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;
}