Go: package main

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

const (
	initialBufSize = 100000
	maxBufSize     = 1000000
)

var sc *bufio.Scanner

func initScanner(r io.Reader) *bufio.Scanner {
	buf := make([]byte, initialBufSize)

	sc := bufio.NewScanner(r)
	sc.Buffer(buf, maxBufSize)
	sc.Split(bufio.ScanWords) // bufio.ScanLines
	return sc
}

func main() {
	sc = initScanner(os.Stdin)
	resolve(parseProblem())
}

type graph struct {
	size  int
	edges [][]int
}

func parseProblem() *graph {
	n := scanInt(sc)
	g := &graph{
		size:  n,
		edges: make([][]int, n),
	}
	for i := 0; i < g.size; i++ {
		_ = scanInt(sc)
		k := scanInt(sc)
		g.edges[i] = make([]int, k)
		for j := 0; j < k; j++ {
			g.edges[i][j] = scanInt(sc) - 1
		}
	}
	return g
}

func resolve(g *graph) {
	ds := make([]int, g.size)
	fs := make([]int, g.size)
	time := 0
	for i := 0; i < len(ds); i++ {
		if ds[i] == 0 {
			time++
			time = _dfs(ds, fs, time, g, i)
		}
	}
	for i := 0; i < len(ds); i++ {
		fmt.Println(i+1, ds[i], fs[i])
	}
	return
}

func _dfs(ds, fs []int, time int, g *graph, idx int) int {
	ds[idx] = time
	for _, next := range g.edges[idx] {
		if ds[next] > 0 {
			continue
		}
		time++
		time = _dfs(ds, fs, time, g, next)
	}
	time++
	fs[idx] = time
	return time
}

// snip-scan-funcs
func scanInt(sc *bufio.Scanner) int {
	sc.Scan()
	i, _ := strconv.Atoi(sc.Text())
	return int(i)
}
func scanString(sc *bufio.Scanner) string {
	sc.Scan()
	return sc.Text()
}

C++: #include <stdio.h>
#define N 100
#define WHITE 0
#define GRAY  1
#define BLACK 2

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]==0) continue;
        if(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(u=0;u<n;u++)
        printf("%d %d %d\n",u+1,d[u],f[u]);
}

int main()
{
    int u,v,k,i,j;
    scanf("%d",&n);
    for(i=0;i<n;i++)
        for(j=0;j<n;j++)
            M[i][j]=0;
    for(i=0;i<n;i++)
    {
        scanf("%d %d",&u,&k);
        u--;
        for(j=0;j<k;j++)
        {
            scanf("%d",&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 nowTime;

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

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);
		}
	}

	for(int i=1; i<=n; i++) {
		if(d[i] ==0) dfsRec(adj, n, i);
	}

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

C++: #include<iostream>
using namespace std;
int size[101],graph[101][100],cnt,times[101],timee[101];

void dfs(int x){
  if(times[x]==0){
    times[x]=++cnt;
    for(int i=0;i<size[x];++i){
      if(times[graph[x][i]]==0) dfs(graph[x][i]);
    }
    timee[x]=++cnt;
  }
}

int main(){
  int n,u,k,v; cin>>n;
  for(int i=0;i<n;++i){
    cin>>u>>k;
    size[u]=k;
    for(int j=0;j<k;++j){
      cin>>v;
      graph[u][j]=v;
    }
  }
  for(int i=1;i<=n;++i) dfs(i);
  for(int i=1;i<=n;++i) cout<<i<<" "<<times[i]<<" "<<timee[i]<<endl;
  return 0;
}

C++: #include <iostream>
#include <string>
#include <map>
#include <stack>
#include <algorithm>
using namespace std;
#define MAX 100000

static const int N=100;
static const int WHITE=0;
static const int GRAY=1;
static const int BLACK=2;

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

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

void dfs_visit(int r){
  for(int i=0;i<n;i++) nt[i]=0;
  stack<int> S;
  S.push(r);
  color[r]=GRAY;
  d[r]=++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;
    nt[i]=0;
  }
  tt=0;

  for(int 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
//------------------------------------------
#include <bits/stdc++.h>
//DEFINE
//------------------------------------------
#define ll long long
#define ld long double
#define ALLv(a)  (a).begin(),(a).end()
#define ALL(a,n)  (a),(a)+n
#define vi vector<long long>
#define vd vector<long double>
#define vs vector<string>
#define dcml(n) fixed<<setprecision(n)
//CONST
//------------------------------------------
const ll INF=1010000000000000017LL;
const ll MOD=1000000007LL;
const ld EPS=1e-12;
const ld PI=3.14159265358979323846;
//REPEAT
//------------------------------------------
#define   FOR(i,m,n) for(ll (i)=(m);   (i)<(n);  (i)++)
#define  FORS(i,m,n) for(ll (i)=(m);   (i)<=(n); (i)++)
#define  RFOR(i,m,n) for(ll (i)=(n)-1; (i)>=(n); (i)--)
#define RFORS(i,m,n) for(ll (i)=(n);   (i)>(n);  (i)--)
#define   REP(i,n)   for(ll (i)=0;     (i)<(n);  (i)++)
#define  REPS(i,x)   for(ll (i)=1;     (i)<=(x); (i)++)
#define  RREP(i,x)   for(ll (i)=(x)-1; (i)>=0;   (i)--)
#define RREPS(i,x)   for(ll (i)=(x);   (i)> 0;   (i)--)
#define  WREP(i,in,j,jn) REP(i,in)REP(j,jn)
#define WREPS(i,in,j,jn) REPS(i,in)REPS(j,jn)
//-----------------------------------------
//namespace
using namespace std;
//ライブラリはここに
//↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓↓

//-----------------------------------------
vector<ll> G[110];
bool done[110];
ll START[110],END[110];
ll t=1;
void dfs(ll from){
    done[from]=true;
    if(START[from]==-1) START[from]=t++;
    for(auto r:G[from]){
        if(done[r])continue;
        dfs(r);
    }
    if(END[from]==-1) END[from]=t++;
}
int main(void){
    ll N;cin>>N;
    REP(i,N){
        START[i]=END[i]=-1;
        done[i]=false;
    }
    REP(i,N){
        ll idx;cin>>idx;ll k;cin>>k;
        REP(j,k){
            ll to;cin>>to;to--;
            G[i].push_back(to);
        }
    }
    REP(i,N) dfs(i);
    REP(i,N){
        printf("%lld %lld %lld\n",i+1,START[i],END[i]);
    }
}

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

typedef long long ll;

vector<vector<ll>> graph(100);
vector<bool> visit(100,false);
vector<ll> d(100);
vector<ll> f(100);
ll tmp = 0;

void dfs(ll v)
{
    ll i;
    visit.at(v) = true;
    d.at(v) = ++tmp;
    for(i = 0;i < graph.at(v).size();++i){
        ll g = graph.at(v).at(i);
        if(visit.at(g)){
            continue;
        }
        dfs(g);
    }
    f.at(v) = ++tmp;
    return;
}

int main()
{
    ll i,j;
    ll n;
    cin >> n;
    for(i = 0;i < n;++i){
        ll u,k;
        cin >> u >> k;
        for(j = 0;j < k;++j){
            ll v;
            cin >> v;
            graph.at(u-1).push_back(v-1);
        }
    }
    for(i = 0;i < n;++i){
        if(!visit.at(i)){
            dfs(i);
        }
    }
    for(i = 0;i < n;++i){
        cout << i+1 << " " << d.at(i) << " " << f.at(i) << endl;
    }
    return 0;
}