Go: package main

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

// I/O
type Scanner struct {
	sc *bufio.Scanner
}

func NewScanner() *Scanner {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)
	sc.Buffer(make([]byte, 1024), int(1e+9))
	return &Scanner{sc}
}

func (s *Scanner) nextStr() string {
	s.sc.Scan()
	return s.sc.Text()
}

func (s *Scanner) nextInt() int {
	i, e := strconv.Atoi(s.nextStr())
	if e != nil {
		panic(e)
	}
	return i
}

func (s *Scanner) nextFloat() float64 {
	f, e := strconv.ParseFloat(s.nextStr(), 64)
	if e != nil {
		panic(e)
	}
	return f
}

func (s *Scanner) nextRuneSlice() []rune {
	return []rune(s.nextStr())
}

func (s *Scanner) nextIntSlice(n int) []int {
	res := make([]int, n)
	for i := 0; i < n; i++ {
		res[i] = s.nextInt()
	}
	return res
}

func (s *Scanner) nextFloatSlice(n int) []float64 {
	res := make([]float64, n)
	for i := 0; i < n; i++ {
		res[i] = s.nextFloat()
	}
	return res
}

// Arithmetic
func max(nums ...int) int {
	m := nums[0]
	for _, i := range nums {
		if m < i {
			m = i
		}
	}
	return m
}

func min(nums ...int) int {
	m := nums[0]
	for _, i := range nums {
		if m > i {
			m = i
		}
	}
	return m
}

func abs(x int) int {
	if x > 0 {
		return x
	}
	return -x
}

func pow(x, y int) int {
	res := 1
	for i := 0; i < y; i++ {
		res *= x
	}
	return res
}

func ceil(a, b int) int {
	if a%b == 0 {
		return a / b
	} else {
		return a/b + 1
	}
}

// Sort
type RuneSlice []rune

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

// Main
func main() {
	sc := NewScanner()
	wtr := bufio.NewWriter(os.Stdout)
	N := sc.nextInt()
	G := make([][]int, N)
	for i := 0; i < N; i++ {
		u, k := sc.nextInt()-1, sc.nextInt()
		for j := 0; j < k; j++ {
			G[u] = append(G[u], sc.nextInt()-1)
		}
	}
	ans := make([][2]int, N)
	time := 0
	found := make(map[int]bool)
	var dfs func(cur int)
	dfs = func(cur int) {
		time++
		ans[cur][0] = time
		found[cur] = true
		for i := 0; i < len(G[cur]); i++ {
			next := G[cur][i]
			if !found[next] {
				dfs(G[cur][i])
			}
		}
		time++
		ans[cur][1] = time
	}
	for i := 0; i < N; i++ {
		if !found[i] {
			dfs(i)
		}
	}

	for i := 0; i < N; i++ {
		fmt.Fprint(wtr, i+1)
		for j := 0; j < 2; j++ {
			fmt.Fprint(wtr, " ")
			fmt.Fprint(wtr, ans[i][j])
		}
		fmt.Fprintln(wtr)
	}
	wtr.Flush()
}

C++: #include <bits/stdc++.h>
using namespace std;
using pii=pair<int,int>;
using ll=long long;
using pll=pair<ll,ll>;

#define fi first
#define se second
#define pb push_back
#define rep(i,n) for(int i=0; i<(int)(n); i++)
#define MOD 1000000007

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; }

int N;
vector<vector<int>> G(110, vector<int>());
vector<int> d(110), f(110), k(110);
vector<bool> visited(110, false);
int t = 0;

void dfs(int v) {
	visited[v] = true;
	d[v] = t;
	//cout << v << " d[" << v << "]:" << d[v] << " " << t << endl;
	rep(i, k[v]) {
		if(visited[G[v][i]]) continue;
		t++;
		//cout << G[v][i] << " " << t << endl;
		dfs(G[v][i]);
		//cout << G[v][i] << " " << t << endl;
	}
	t++;
	f[v] = t;
	//cout << v << " f[" << v << "]:" << f[v] << endl;
	return;
}

int main() {
	cin >> N;
	rep(i,N) {
		int u;
		cin >> u >> k[i];
		G[i] = vector<int>(k[i]);
		rep(j,k[i]) {
			cin >> G[i][j];
			G[i][j]--;
		}
	}
	rep(i,N) {
		if(visited[i] == false) t++,dfs(i);
	}
	rep(i,N) cout << i+1 << " " << d[i] << " " << f[i] << endl;


  return 0;
}

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

int G[105][105]={};
int d[105]={},f[105]={};
int N,T=0;

void Gprint(int n){
    cout<<"\\|";
    for(int i=0; i<n; i++)cout<<i+1;
    cout<<endl;
    for(int i=0; i<n+2; i++)cout<<"-";
    cout<<endl;
    for(int i=0; i<n; i++){
        cout<<i+1<<"|";
        for(int j=0; j<n; j++){
            cout<<G[i][j];
        }
        cout<<endl;
    }
}

void dfs(int n){
    if(d[n])return;
    d[n]=++T;
    for(int i=0; i<N; i++){
        if(G[n][i])dfs(i);
    }
    f[n]=++T;
}

int main(){
    int u,k,v;

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

   Gprint(N);

    for(int i=0; i<N; i++)
        dfs(i);

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

C++: #include <cstdio>
#include <iostream>

using namespace std;

//4
//1 1 2
//2 1 4
//3 0
//4 1 3

//1 1 8
//2 2 7
//3 4 5
//4 3 6

const int MAX = 100;

int n;

int t = 0;

int G[MAX + 1][MAX + 1];
int d[MAX + 1];
int f[MAX + 1];

int color[MAX + 1];
int WHITE = 0;
int GRAY = 1;
int BLACK = 2;

void dfs(int v) {
	color[v] = GRAY;
	d[v] = ++t;

	for (int i = 1; i <= n; ++i) {
		if (G[v][i] == 1 && color[i] == WHITE)
			dfs(i);
	}

	color[v] = BLACK;
	f[v] = ++t;
}

int main() {

	scanf("%d", &n);

	for (int i = 0; i <= n; ++i) {
		for (int j = 0; j <= n; ++j)
			G[i][j] = 0;
	}

	for (int i = 1; i <= n; ++i) {
		int u, k;
		scanf("%d %d", &u, &k);
		for (int j = 0; j < k; ++j) {
			int v;
			scanf("%d", &v);
			G[i][v] = 1;
		}
	}

	dfs(1);

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

	return 0;

}

C++: #include <set>
#include <map>
#include <list>
#include <queue>
#include <stack>
#include <cmath>
#include <ctime>
#include <cstdio>
#include <vector>
#include <string>
#include <bitset>
#include <cctype>
#include <cstdlib>
#include <cstring>
#include <utility>
#include <numeric>
#include <complex>
#include <sstream>
#include <fstream>
#include <iomanip>
#include <cassert>
#include <iostream>
#include <iterator>
#include <algorithm>
using namespace std;
using ll = long long;
using VL=vector<ll>;

#define REP(i, n) for(int i = 0;i < n;i++)
#define REPR(i, n) for(int i = n;i >= 0;i--)
#define FOR(i, m, n) for(int i = m;i < n;i++)
const long long INF =  999999999;
const int WHITE=0;
const int GREY=1;
const int BLACK=2;

int color[110],tt,n,d[110],f[110];
vector<int> g[110];

void dfs_visit(int v){
  color[v]=GREY;
  d[v]=++tt;
  REP(i,g[v].size()){
    if(color[g[v][i]]==WHITE){
      dfs_visit(g[v][i]);
    }
  }
  color[v]=BLACK;
  f[v]=++tt;
}

void dfs(){
  REP(i,n){
    color[i]=WHITE;
  }
  REP(i,n){
    if(color[i]==WHITE)dfs_visit(i);
  }

  REP(i,n){
    printf("%d %d %d\n",i+1,d[i],f[i]);
  }
}

int main(){
  cin  >>n;
  int u,k;
  REP(i,n){
    cin >>u>>k;
    u--;
    REP(i,k){
      int p;
      cin >>p;
      p--;
      g[u].push_back(p);
    }
  }
  tt=0;

  dfs();
}