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 <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <iostream>
#include <string>
#include <vector>
#include <map>
#include <set>
#include <stack>
#include <list>
#include <queue>
#include <deque>
#include <algorithm>
#include <numeric>
#include <utility>
#include <complex>
#include <functional>
#include <climits>

using namespace std;
vector<int> v[101];
int d[101] = {0};
int f[101] = {0};
int t = 0;
void dfs(int id) {
    //d mark
    d[id] = t;
    t++;
    for(int adj: v[id]) {
        if(d[adj] == 0) {
            dfs(adj);
            t++;
        }
    }
    f[id] = t;
}

int main() {
    int n;
    cin >> n;
    for(int i=1; i<=n; i++) {
        int u, k;
        cin >> u >> k;
        for(int j=0; j<k; j++) {
            int adj;
            cin >> adj;
            v[i].push_back(adj);
        }
    }
    for(int i=1; i<=n; i++) {
        if(d[i] == 0) {
            t++;
            dfs(i);
        }
    }

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

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

using namespace std;
using LL = long long;
using P = pair<int, int>;

#define FOR(i, a, n) for(int i = (int)(a); i < (int)(n); ++i)
#define REP(i, n) FOR(i, 0, n)

#define pb(a) push_back(a)
#define all(x) (x).begin(),(x).end()

const int INF = (int)1e9;
const LL INFL = (LL)1e19;
const int MOD = 1e9 + 7;

using Graph = vector<vector<int>>;

int dfs(Graph &graph, vector<int> &d, vector<int> &f, int cur, int time)
{
    if(d[cur] > 0) return time;
    d[cur] = time;
    time++;
    for(int child : graph[cur])
    {
        time = dfs(graph, d, f, child, time);
    }
    f[cur] = time;
    time++;
    return time;
}

signed main()
{
    cin.tie(0);
    ios::sync_with_stdio(false);
    
    int n;
    cin >> n;
    Graph graph(n);
    REP(i, n) 
    {
        int u, k;
        cin >> u >> k;
        REP(j, k) 
        {
            int v;
            cin >> v;
            graph[u-1].push_back(v-1);
        }
    }

    vector<int> d(n, 0), f(n, 0);
    int time = 1;
    REP(i, n)
    {
        if(d[i] > 0) continue;
        time = dfs(graph, d, f, i, time);
    }

    REP(i, n)
    {
        cout << i+1 << " " << d[i] << " " << f[i] << endl;
    }
}

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

int G[101][102];
int found[101];
int comp[101];   // complete.
int t;  // time.

typedef struct box{ int val; box* next; } box_t;  // stack.

box_t* init()
{
    box_t* head = new box_t;
    head->val = -1;
    head->next = NULL;
    return head;
}

bool isEmpty(box_t* head){ return (head->next == NULL ? true : false); }

box_t* push(box_t* head, int data)
{
    box_t* box = new box_t;
    box->val = data;
    box->next = head->next;
    head->next = box;
    return box;
}

int pop(box_t* head)
{
    if(isEmpty(head)){ return -1; }
    box_t* box = head->next;
    int val;
    head->next = box->next;
    val = box->val;
    delete box;
    return val;
}

int front(box_t* head)
{
    int val;
    if(isEmpty(head)){ return -1; }
    val = head->next->val;
    return val;
}

box_t* stack = init();

void search_loop(int i)
{
    int j, k;
    while(1){
        if(found[i] == 0){
            t++; found[i] = t;
            push(stack, i);
        }
        for(k = G[i][0]; G[i][k] != 0 && found[G[i][k]] != 0; k++);
        if(G[i][k] == 0){
            if(isEmpty(stack)){ return; }
            else{
                j = pop(stack);
                t++; comp[j] = t;
                i = front(stack);
            }
        }else{
            G[i][0] = k + 1;
            i = G[i][k];
        }
    };
    return;
}

int main()
{
    int n, i, j, a, b, e;
    cin >> n;
    for(i = 1; i <= n; i++){
        G[i][0] = 1;
        for(j = 1; j <= n + 1; j++){ G[i][j] = 0; } }

    for(i = 1; i <= n; i++){
        cin >> a >> e;
        for(j = 1; j <= e; j++){
            cin >> b; G[a][j] = b; } }  // adjacent representation.

    for(i = 1; i <= n; i++){ found[i] = 0; comp[i] = 0; }
    t = 0;
    while(1){
        for(i = 1; i <= n; i++){
            if(found[i] == 0) break;
        }
        if(i > n) break;
        search_loop(i);
    };

    for(i = 1; i <= n; i++){
        cout << i << " " << found[i] << " " << comp[i] << endl;
    }
    return 0;
}

C++: #include<bits/stdc++.h>
using namespace std;

struct Graph{
	
	vector<char> seen;
	vector<vector<int>> e;
	vector<int> time1,time2; 
	Graph(int n) : seen(n),e(n),time1(n),time2(n){}
	
	void dfs(int v, int &t){
		t++;
		time1.at(v) = t;
		seen.at(v) = 1;
		for(auto nv:e.at(v)) {
			if(seen.at(nv)==1) continue;
			dfs(nv,t);
		}
		t++;
		time2.at(v) = t;
		return;
	}
	
};

int main() {
	
	int n;
	cin >> n;
	Graph graph(n);
	for(int i=0; i<n; i++){
		int u,k;
		cin >> u >> k;
		for(int j=0; j<k; j++){
			int v;
			cin >> v;
			v--;
			graph.e.at(i).push_back(v);
		}
	}
	
	int t={};
	for(int i=0; i<n; i++){
		if(graph.seen.at(i)!=1) graph.dfs(i,t);
	}
	
	for(int i=0; i<n; i++){
		cout << i+1 << ' ' << graph.time1.at(i) << ' ' << graph.time2.at(i) << endl;
	}
	
	
}