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 <map>
#include <set>
#include <list>
#include <cmath>
#include <queue>
#include <stack>
#include <cstdio>
#include <string>
#include <vector>
#include <complex>
#include <cstdlib>
#include <cstring>
#include <numeric>
#include <sstream>
#include <iostream>
#include <algorithm>
#include <functional>
 
#define mp       make_pair
#define pb       push_back
#define all(x)   (x).begin(),(x).end()
#define rep(i,n) for(int i=0;i<(n);i++)
 
using namespace std;
 
typedef    long long          ll;
typedef    unsigned long long ull;
typedef    vector<bool>       vb;
typedef    vector<int>        vi;
typedef    vector<vb>         vvb;
typedef    vector<vi>         vvi;
typedef    pair<int,int>      pii;
 
const int INF=1<<29;
const double EPS=1e-9;
 
const int dx[]={1,0,-1,0},dy[]={0,-1,0,1};

int count = 1;
std::vector<vector<int> > G;
std::vector<int> flag;
std::vector<int> in;
std::vector<int> out;
int N;
int dfs(int u, int count) {
	flag[u] = 1;
	
	in[u] = count;
	for (int i = 0; i < N; ++i) {
		if (flag[i] == 0 && G[u][i] == 1) {
			count = dfs(i, count + 1);
		}
	}
	out[u] = count + 1;
	return count + 1;
}

int main(int argc, char const *argv[]) {
	
	cin >> N;

	for (int i = 0; i < N; ++i) {
		G.push_back(vector<int>());
		flag.push_back(0);
		in.push_back(0);
		out.push_back(0);
		for (int j = 0; j < N; ++j) {
			G[i].push_back(0);
		}
	}

	for (int i = 0; i < N; ++i) {
		int u, k;
		cin >> u >> k;
		u--;
		for (int j = 0; j < k; ++j) {
			int v;
			cin >> v;
			v--;
			G[u][v] = 1;
		}
	}

	dfs(0, 1);

	for (int i = 0; i < N; ++i) {
		cout << i + 1 << " " << in[i] << " " << out[i] << endl;
	}

	return 0;
}

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

int Stime = 0;
vector<int> edges[100];
bool visit[100];
int be[100]; //begin
int en[100]; //end


void dfs(int cur) //curを訪問
{
	//curの訪問時間を記録
	Stime++;
	visit[cur] = true;

	//cout << "visiting " << cur+1 << "  time:" << time << endl;
	be[cur] = Stime;

	for (int i = 0; i < edges[cur].size(); ++i)
	{
		if (!visit[edges[cur][i]])
		{
			dfs(edges[cur][i]);
		}
	}

	Stime++;

	//cout << "finished visiting " << cur+1 << "  time:" << time << endl;
	en[cur] = Stime;

}
int main()
{
	int n;
	cin >> n;
	for (int i = 0; i < 100; ++i)
	{
		visit[i] = false;
	}

	int u,k,v;
	for (int i = 0; i < n; ++i)
	{
		cin >> u >> k;

		for (int j = 0; j < k; ++j)
		{
			cin >> v;
			edges[i].push_back(v-1);
		}
	}

	int temp = 0;
	int flag = true; //未探索のノードがあるかどうか
	while(flag)
	{
		dfs(temp);
		flag = false;
		for (int i = 0; i < n; ++i)
		{
			if (!visit[i])
			{
				temp = i;
				flag = true;
				break;
			}
		}
	}

	for (int i = 0; i < n; ++i)
	{
		cout << i+1 << " " << be[i] << " " << en[i] << endl;
	}
	return 0;
}

C++: #define _GLIBCXX_DEBUG
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define ALL(v) v.begin(), v.end()
typedef long long ll;

template<class T>bool chmax(T &a, const T &b) { if (a<b) { a=b; return 1; } return 0; }
template<class T>bool chmin(T &a, const T &b) { if (b<a) { a=b; return 1; } return 0; }

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

#define white 0
#define gray 1

int M[110][110];
vector<int> color(110,white),d(110),f(110);
int t=0;
int n;

void dfs(int u){
  color[u]=gray;
  d[u]=++t;
  for(int v=0;v<n;v++){
    if(M[u][v] && color[v]==white) dfs(v);
  }
  f[u]=++t;
}

int main(){
  cin>>n;
  
  rep(i,n){
    rep(j,n) M[i][j]=0;
  }
  
  int x,y,z;
  rep(i,n){
    cin>>x>>y;
    x--;
    rep(j,y){
      cin>>z;
      z--;
      M[x][z]=1;
    }
  }

  rep(i,n){
    if(color[i]==white) dfs(i);
  }
  
  rep(i,n) cout<<i+1<<" "<<d[i]<<" "<<f[i]<<endl;
  
  return 0;
}