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++: /**
 * Depth first search.
 * start from node 1
 * 1) increment time 
 * 2) find non visited adjacent node
 * 3) if found move to that node.  d[v'] = time
 * 4) if not found. f[v] = time
 * 5) else end.
 * 5) go to 2.
 */

#include <iostream>
using namespace std;
const int N = 101;
int adj[N][N] = {0};
int d[N]={0};
int f[N]={0};
int t = 1;

void dfs(int n) {
	if (d[n]) return;
	d[n]=++t;
	int k = adj[n][0];
	for (int j=1;j<=k;j++) {
		dfs(adj[n][j]);
	}
	f[n]=++t;
}

int main()
{
	int n;
	cin >> n;
	for (int i=1;i<=n;i++){
		int j, k;
		cin >> j >> k;
		adj[j][0]=k;
		for (int m=1;m<=k;m++) {
			int a;
			cin >> a;
			adj[j][m]=a;
		}
	}

	for (int i=1;i<=n;i++){
		dfs(i);
	}

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

	return 0;
}

C++: #include <cstdio>
#include <vector>
using namespace std;

void dfs(int cur, vector<vector<int> > arr, int d[], int f[], int &time, int n, bool psd[]){
    d[cur] = time;
    time++;
    psd[cur] = true;
    for(int dst = 0; dst < n; dst++){
        if(arr[cur][dst] == 1 && !psd[dst]){
            dfs(dst,arr,d,f,time,n,psd);
        }
    }
    f[cur] = time;
    time++;
}

int main(){
    int n;
    scanf("%d",&n);
    vector<vector<int> > arr(n,vector<int>(n));
    for(int i = 0; i < n; i++){
        for(int j = 0; j < n; j++){
            arr[i][j] = 0;
        }
    }
    for(int i = 0; i < n; i++){
        int u,k;
        scanf("%d %d",&u,&k);
        for(int j = 0; j < k; j++){
            int v;
            scanf("%d",&v);
            arr[u-1][v-1] = 1;
        }
    }
    int d[n],f[n],time = 1;
    bool psd[n];
    for(int i = 0; i < n; i++){
        psd[i] = false;
    }
    for(int cur = 0; cur < n; cur++){
        if(!psd[cur]){
            dfs(cur,arr,d,f,time,n,psd);
        }
    }
    for(int id = 0; id < n; id++){
        printf("%d %d %d\n", id+1, d[id], f[id]);
    }
}

C++: #include <stdio.h>
#include <iostream>
using namespace std;

class Adjl{
private:
	int u;
	int k;
	Adjl **next;
protected:
	int d;
	int f;
public:
	Adjl(int u);
	~Adjl(){ if (next != NULL) delete[] next; }
	void setV(int k, Adjl *vk);
	int depthFirstSearch(int time);
	void print();
};

Adjl::Adjl(int u)
{
	this->u = u;
	k = 0;
	next = NULL;
	d = 0;
	f = 0;
}

void Adjl::setV(int k, Adjl *vk)
{
	if (this->k == 0) next = new Adjl*[k];
	next[this->k] = vk;
	(this->k)++;
}

int Adjl::depthFirstSearch(int time)
{
	time++;
	d = time;
	for (int i = 0; i < k; i++) {
		if (next[i]->d == 0) {
			time = next[i]->depthFirstSearch(time);
		}
	}
	time++;
	f = time;
	return time;
}

void Adjl::print()
{
	cout << u << " " << d << " " << f << endl;
}

int main(void)
{
	int n;
	cin >> n;
	
	Adjl **adjl = new Adjl*[n];
	int check[100] = {0};

	for (int i = 0; i < n; i++) {
		int u, k;
		cin >> u >> k;
		if (check[i] == 0) {
			adjl[i] = new Adjl(u);
			check[i] = 1;
		}
		check[i] = 1;
		for (int j = 0; j < k; j++) {
			int vk;
			cin >> vk;
			if (check[vk - 1] == 0) {
				adjl[vk - 1] = new Adjl(vk);
				check[vk - 1] = 1;
			}
			adjl[i]->setV(k, adjl[vk - 1]);
		}
	}

	adjl[0]->depthFirstSearch(0);

	for (int i = 0; i < n; i++) {
		adjl[i]->print();
	}

	delete[] adjl;
	return 0;
}

C++: #include <bits/stdc++.h>
#define rep(i,n) for(int i=0; i<(n); i++)
#define FOR(i,a,n) for(int i=(a); i<(n); i++)
#define all(v) v.begin(), v.end()
using namespace std;
typedef long long ll;
const int INF = 1e9;
const int MOD = 1e9+7;

using Graph = vector<vector<int>>;
Graph G;

vector<int> d, f;

int dfs(int v, int t) {
    if(d[v]==0) d[v]=t;
    int res = t;
    for(const auto nv: G[v]) {
        if (d[nv]) continue;
        res = dfs(nv, res+1);
    }
    return f[v] = ++res;
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);

    int n; cin >> n;
    G.resize(n);
    rep(i, n) {
        int x, k; cin >> x >> k;
        x--;
        rep(j, k) {
            int v; cin >> v; v--;
            G[x].push_back(v);
        }
    }

    d.assign(n, 0); f.assign(n, 0);

    int cur = 1;
    rep(i, n) {
        if (!d[i]) {
            cur = dfs(i, cur);
            cur++;
        }
    }
    rep(i, n) {
        cout << i+1 << " " << d[i] << " " << f[i] << endl;
    }
}