Go: package main

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

func getScanner(fp *os.File) *bufio.Scanner {
	scanner := bufio.NewScanner(fp)
	scanner.Split(bufio.ScanWords)
	scanner.Buffer(make([]byte, 1000005), 1000005)
	return scanner
}

func getNextString(scanner *bufio.Scanner) string {
	scanner.Scan()
	return scanner.Text()
}

func getNextInt(scanner *bufio.Scanner) int {
	i, _ := strconv.Atoi(getNextString(scanner))
	return i
}

func getNextInt64(scanner *bufio.Scanner) int64 {
	i, _ := strconv.ParseInt(getNextString(scanner), 10, 64)
	return i
}

func getNextUint64(scanner *bufio.Scanner) uint64 {
	i, _ := strconv.ParseUint(getNextString(scanner), 10, 64)
	return i
}

func getNextFloat64(scanner *bufio.Scanner) float64 {
	i, _ := strconv.ParseFloat(getNextString(scanner), 64)
	return i
}

func main() {
	fp := os.Stdin
	wfp := os.Stdout
	cnt := 0

	if os.Getenv("MASPY") == "ますピ" {
		fp, _ = os.Open(os.Getenv("BEET_THE_HARMONY_OF_PERFECT"))
		cnt = 1
	}
	if os.Getenv("MASPYPY") == "ますピッピ" {
		wfp, _ = os.Create(os.Getenv("NGTKANA_IS_GENIUS10"))
	}

	scanner := getScanner(fp)
	writer := bufio.NewWriter(wfp)
	solve(scanner, writer)
	for i := 0; i < cnt; i++ {
		fmt.Fprintln(writer, "-----------------------------------")
		solve(scanner, writer)
	}
	writer.Flush()
}

func solve(scanner *bufio.Scanner, writer *bufio.Writer) {
	n := getNextInt(scanner)
	g := graph{}
	g.ee = make([]Edges, n)
	g.visited = make([]bool, n)
	g.found = make([]int, n)
	g.leave = make([]int, n)
	for i := 0; i < n; i++ {
		u := getNextInt(scanner) - 1
		k := getNextInt(scanner)
		for j := 0; j < k; j++ {
			v := getNextInt(scanner) - 1
			g.ee[u] = append(g.ee[u], Edge{
				to: v,
				id: u,
			})
		}
	}
	for i := 0; i < n; i++ {
		sort.Sort(g.ee[i])
	}
	for i := 0; i < n; i++ {
		if g.visited[i] {
			continue
		}
		g.dfs(i)
	}

	for i := 0; i < n; i++ {
		fmt.Fprintln(writer, fmt.Sprintf("%d %d %d", i+1, g.found[i], g.leave[i]))
	}
}

// Edge ...
type Edge struct {
	to, id int
}

type Edges []Edge

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

type graph struct {
	ee           []Edges
	t            int
	n            int
	visited      []bool
	found, leave []int
}

func (g *graph) dfs(i int) {
	g.visited[i] = true
	g.t++
	g.found[i] = g.t
	for _, e := range g.ee[i] {
		if g.visited[e.to] {
			continue
		}
		g.dfs(e.to)
	}
	g.t++
	g.leave[i] = g.t
}

C++: #include <iostream>
#include <vector>
#include <algorithm>
#define N 2000

using namespace std;
vector<vector<int> > pa;
vector<vector<int> > ch;
int first[N] = {0};
int second[N] = {0};
int timestamp = 0;
void dfs(int x) {
    if (ch[x].empty()) {
        return;
    } else {
        for (int i = 0; i < ch[x].size(); i++) {
            if (first[ch[x][i]] == 0 && second[ch[x][i]] == 0) {
                timestamp++;
                first[ch[x][i]] = timestamp;
                dfs(ch[x][i]);
                timestamp++;
                second[ch[x][i]] = timestamp;
            }
        }
        return;
    }
}
int main() {
    int n;
    cin >> n;
    int temp = n;
    pa.clear(); pa.resize(N + 5);
    ch.clear(); ch.resize(N + 5);
    while (temp--) {
        int u, k, v;
        cin >> u >> k;
        for (int i = 0; i < k; i++) {
            cin >> v;
            pa[v].push_back(u);
            ch[u].push_back(v);
        }
    }
    int an = 0;
    for (int i = 1; i <= n; i++) {
        if (pa[i].empty()) {
            an = i;
        } else {
            sort(pa[i].begin(), pa[i].end(), less<int>());
        }
        if (ch[i].empty()) {
            ;
        } else {
            sort(ch[i].begin(), ch[i].end());
        }
    }
    timestamp++;
    first[an] = timestamp;
    dfs(an);
    timestamp++;
    second[an] = timestamp;
    for (int i = 1; i <= n; i++) {
        cout << i << ' ' << first[i] << ' ' << second[i] << '\n';
    }
}

// int main(){
//     for (int i = 1 ; i <= n ; i++)
//         if (discovered[i] == -1)
//             dfs(i);
// }
// 
// void dfs(int cur){
//     discovered[cur] = stamp++;
//     for (int i = 0 ; i < pa[cur].size() ; i++)
//         if (discovered[cur] == -1)
//             dfs(pa[cur][i]);
//     visited[cur] = stamp++;
// }

C++: #include<iostream>
#include<stack> 
const int MAXN = 105;
const int WHITE = 0;
const int GRAY = 1;
const int BLACK = 2;
int a[MAXN][MAXN];
int color[MAXN];
int d[MAXN];
int f[MAXN];
int nt[MAXN];
int n, tt = 0;
using namespace std;

int next(int u)
{
	for(int v = nt[u]; v < n; v++)
	{
		nt[u] = v + 1;
		if(a[u][v])
			return v;		
	}
	return -1;
}

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

int main ()
{
	int k, u, temp;
	cin >> n;
	for(int i = 0; i < n; i++)
	{
		cin >> u >> k;
		u--;
		for(int j = 0; j < k; j++)
		{
			cin >> temp;
			temp--;
			a[u][temp] = 1;
		}
	}
	dfs_init();
	return 0;
}

C++: #include <iostream>
#include <string>
#include <vector>
#include <functional>
#include <algorithm>
#include <array>
#include <stack>
#include <tuple>

using namespace std;

template<typename ISTREAM>
void readGraphListAsMatrix(const size_t n, ISTREAM& cin, vector< vector<int> >& graphMatrix) {
	graphMatrix = vector< vector<int> >(n, vector<int>(n, 0));
	for (size_t i = 0; i != n; ++i) {
		size_t u;
		size_t k;
		cin >> u;
		cin >> k;
		for (size_t j = 0; j != k; ++j) {
			size_t v;
			cin >> v;
			graphMatrix.at(u - 1).at(v - 1) = 1;
		}
	}
}

void printMatrix(const vector< vector<int> >& graphMatrix) {
	const size_t n = graphMatrix.size();
	for (size_t i = 0; i != n; ++i) {
		const vector<int>& adj = graphMatrix.at(i);
		cout << adj.front();
		for (size_t j = 1; j != n; ++j) {
			cout << " " << adj.at(j);
		}
		cout << endl;
	}
}

template<typename T>
void execute(T& cin) {
	size_t n;
	cin >> n;
	vector< vector<int> > graphMatrix;
	readGraphListAsMatrix(n, cin, graphMatrix);
	stack<size_t> visitedNodeIDs;
	vector<vector<int>::iterator> searchBeginPos;
	searchBeginPos.reserve(n);
	for (auto& v : graphMatrix)searchBeginPos.push_back(v.begin());
	int time = 0;
	vector<pair<int, int>> timeStamp(n,make_pair(0,0));//pair<初回訪問時刻, 完了時刻>
	for (int i = 0; i != n; ++i) {
		pair<int, int>& dp = timeStamp.at(i);
		if (dp.first != 0)continue;
		visitedNodeIDs.push(i);
		dp.first = ++time;
		while (!visitedNodeIDs.empty()) {
			const int nodeID_1 = visitedNodeIDs.top();
			vector<int>& neighbourNodeList = graphMatrix.at(nodeID_1);
			vector<int>::iterator& searchStart = searchBeginPos.at(nodeID_1);
			while (true) {
				searchStart = find(searchStart, neighbourNodeList.end(),1);
				if (searchStart == neighbourNodeList.end()) {
					timeStamp.at(nodeID_1).second = time + 1;
					visitedNodeIDs.pop();
					break;
				}
				else {
					const size_t nextVisitID_1 = distance(neighbourNodeList.begin(), searchStart);
					++searchStart;
					if (timeStamp.at(nextVisitID_1).first == 0) {
						timeStamp.at(nextVisitID_1).first = time + 1;
						visitedNodeIDs.push(nextVisitID_1);
						break;
					}
				}
			}
			++time;
		}
	}
	for (int i = 0; i != n; ++i) {
		cout << i + 1 << " " << timeStamp.at(i).first << " " << timeStamp.at(i).second << endl;
	}
}

int main()
{

	execute(cin);


	return 0;
}