Go: package main

/*
深さ優先探索
*/

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

func main() {
	scanner := makeScanner(8192)
	n := eGetInt(scanner)
	g := make([][]int, n+1)
	for i := 1; i < n+1; i++ {
		ints := eGetInts(scanner)
		num, vcount := ints[0], ints[1]
		g[i] = make([]int, vcount)
		for j := 0; j < vcount; j++ {
			g[num][j] = ints[j+2]
		}
	}
	hist := make([]struct{ d, f int }, n+1)
	t := 0
	var visit func(int)
	visit = func(num int) {
		if hist[num].d == 0 {
			stack := []int{}
			t++
			hist[num].d = t
			stack = append(stack, num)
			for len(stack) > 0 {
				// トップを訪問する
				top := stack[len(stack)-1]
				for i := 0; i < len(g[top]); i++ {
					if hist[g[top][i]].d == 0 {
						t++
						hist[g[top][i]].d = t
						stack = append(stack, g[top][i])
						goto endloop
					}
				}
				// 訪問場所がなくなったら
				// pop
				stack = stack[0 : len(stack)-1]
				t++
				hist[top].f = t
			endloop:
			}
		}
	}
	for i := 1; i < n+1; i++ {
		visit(i)
	}
	for i := 1; i < n+1; i++ {
		fmt.Println(i, hist[i].d, hist[i].f)
	}
}

////////////////////////////////////////////////////////////////////////////////
// ライブラリ
////////////////////////////////////////////////////////////////////////////////
func makeScanner(maxByte int) *bufio.Scanner {
	scanner := bufio.NewScanner(os.Stdin)
	scanner.Buffer(make([]uint8, 0, 8192), maxByte)
	return scanner
}
func makeWordScanner() *bufio.Scanner {
	scanner := makeScanner(8192)
	scanner.Split(bufio.ScanWords)
	return scanner
}
func eGetLine(r *bufio.Scanner) string {
	if r.Scan() {
		return r.Text()
	}
	err := r.Err()
	if err != nil {
		log.Fatal(err)
	}
	// EOF
	return ""
}
func eGetInt(r *bufio.Scanner) int {
	line := eGetLine(r)
	return eAtoi(line)
}
func eGetInt64(r *bufio.Scanner) int64 {
	line := eGetLine(r)
	return eAtoInt64(line)
}
func eGetFields(r *bufio.Scanner) []string {
	line := eGetLine(r)
	return strings.Fields(line)
}
func eGetInts(r *bufio.Scanner) []int {
	fields := eGetFields(r)
	ints := make([]int, len(fields))
	for i := 0; i < len(ints); i++ {
		ints[i] = eAtoi(fields[i])
	}
	return ints
}
func eGetInt64s(r *bufio.Scanner) []int64 {
	fields := eGetFields(r)
	ints := make([]int64, len(fields))
	for i := 0; i < len(ints); i++ {
		ints[i] = eAtoInt64(fields[i])
	}
	return ints
}
func eGetChars(r *bufio.Scanner) []string {
	line := eGetLine(r)
	return strings.Split(line, "")
}
func eAtoi(s string) int {
	n, err := strconv.Atoi(s)
	if err != nil {
		log.Fatal(err)
	}
	return n
}
func eAtoInt64(s string) int64 {
	n, err := strconv.ParseInt(s, 10, 64)
	if err != nil {
		log.Fatal(err)
	}
	return n
}

C++: #include <iostream>
#define N 100
#define WHITE 0
#define GRAY 1
#define BLACK 2
using namespace std;


int n,m[N][N];
int color[N],d[N],f[N],tt;

void dfs_visit(int u){
	int v;
	color[u]=GRAY;
	d[u] = ++tt;
	for(v=0;v<n;v++){
		if(m[u][v]&&color[v]==WHITE)
		dfs_visit(v);
	}
	color[u] = BLACK;
	f[u] = ++tt;
	
}

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



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

C++: #include <iostream>
#include <string>
#include <vector>
#include <algorithm>
#include <cmath>

using namespace std;

using ll = long long;

#define REP(i,n) for(ll i=0;i<(ll)(n);i++)
#define REPD(i,n) for(ll i=n-1;i>=0;i--)
#define FOR(i,a,b) for(ll i=a;i<=(ll)(b);i++)
#define FORD(i,a,b) for(ll i=a;i>=(ll)(b);i--)

#define input(...) __VA_ARGS__; in(__VA_ARGS__)

template<class T>
void print(vector<T> a) {
  cout << "[ ";
  REP(i, a.size()) cout << a[i] << " ";
  cout << "]" << endl;
}

void print() {
  std::cout << std::endl;
}

template <class Head, class... Tail>
void print(Head&& head, Tail&&... tail) {
  std::cout << head << " ";
  print(std::forward<Tail>(tail)...);
}

void in() { }

template <class Head, class... Tail>
void in(Head&& head, Tail&&... tail) {
  cin >> head;
  in(std::forward<Tail>(tail)...);
}

ll cnt = 0;
vector<pair<ll, ll>> ans;
vector<bool> visited;
void f(ll node, vector<vector<ll>> &graph) {
  if (visited[node]) return;
  visited[node] = true;

  ll found = ++cnt;
  for(ll nxt: graph[node]) {
    f(nxt, graph);
  }
  ll solve = ++cnt;
  ans[node] = {found, solve};
}

int main() {
  ll input(n);
  vector<vector<ll>> graph(n);
  ans = vector<pair<ll, ll>>(n);
  visited = vector<bool>(n);
  REP(i, n) {
    ll input(u, k);
    REP(j, k) {
      ll input(v);
      graph[u - 1].push_back(v - 1);
    }
  }

  REP(i, n) f(i, graph);
  REP(i, n) {
    cout << i + 1 << " " << ans[i].first << " " << ans[i].second << endl;
  }
}

C++: #include<iostream>
#include<stack>
using namespace std;
static const int N = 100; 
static const int WHITE = 0;
static const int GRAY = 1; 
static const int BLACK = 2;

int M[N][N], color[N], d[N], f[N], nt[N];
int tt,n;

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

void dfs_visit(int u) {
	for(int i = 0; i < n; i++) nt[i] = 0;
	
	stack<int> S;
	S.push(u);
	color[u] = BLACK;
	f[u] = ++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() {
	for(int i = 0; i < n; i++){
		color[i] = WHITE; 
	}
	tt = 0; 
	
	for(int j = 0; j < n; j++) {
		if(color[j] == WHITE) {
			dfs_visit(j);
		}
	}
	
	for(int i =0; i < n; i++ ) {
    	cout << i+1 << " " << d[i] << " " << f[i] << endl;
	}
}


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

C++: /*
 * ALDS1_11_B.cpp
 *
 *  Created on: May 5, 2018
 *      Author: 13743
 */

#include<iostream>
#include<vector>

using namespace std;

int d[101];
int f[101];
int time;

void dfsRec(vector<int>* a, int n, int v) {
	if(d[v] > 0) return;
	time++;
	d[v] = time;
	for(int &x:a[v]) {
		dfsRec(a, n, x);
	}
	time++;
	f[v] = time;
}

int main() {
	int n;
	vector<int> adj[101];

	cin >> n;
	for(int i=0; i<n; i++) {
		int v;
		int k;
		cin >> v >> k;
		for(int j=0; j<k; j++) {
			int u;
			cin >> u;
			adj[v].push_back(u);
		}
	}

	dfsRec(adj, n, 1);

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

C++: #include <bits/stdc++.h>
#ifdef _DEBUG
#include "debug.hpp"
#else
#define debug(...)
#endif
#define REP(i, m, n) for(int (i) = (m); (i) < (n); ++i)
#define rep(i, n) REP(i, 0, n)
#define rrep(i, n) for(int (i) = (n)-1; (i) >= 0; --i)
#define all(x) (x).begin(), (x).end()
#define FI first
#define SE second
using namespace std;
typedef long long ll;
typedef pair<int, int> P;
const int INF = 1e9+7;
const ll LINF = 1LL<<60;
template <class T, class U>
inline bool chmax(T &a, const U &b) {
  if(a < b) {
    a = b;
    return true;
  }
  return false;
}
template <class T, class U>
inline bool chmin(T &a, const U &b) {
  if(a > b) {
    a = b;
    return true;
  }
  return false;
}

int n;
vector<vector<int>> g;
vector<int> d, f;
vector<bool> vis;

void dfs(int v, int &t) {
  if(vis[v]) return;
  vis[v] = true;
  d[v] = t++;
  for(int u : g[v]) {
    dfs(u, t);
  }
  f[v] = t++;
}

int main() {
  cin.tie(0); ios::sync_with_stdio(false);
  cin >> n;
  g.resize(n);
  vis.resize(n, false);
  rep(i,n) {
    int u, k;
    cin >> u >> k;
    --u;
    rep(j,k) {
      int v;
      cin >> v;
      --v;
      g[u].push_back(v);
    }
  }
  d.resize(n); f.resize(n);
  int t = 1;
  rep(i,n) dfs(i, t);
  rep(i,n) {
    cout << i+1 << " " << d[i] << " " << f[i] << '\n';
  }
  return 0;
}