Go: package main

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

//util
var sc = bufio.NewScanner(os.Stdin)

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

func nextInt() int {
	sc.Scan()
	i, e := strconv.Atoi(sc.Text())
	if e != nil {
		panic(e)
	}
	return i
}

func printList(list []int) {
	n := len(list)
	buf := bufio.NewWriter(os.Stdout)
	for _, v := range list[0 : n-1] {
		buf.Write([]byte(fmt.Sprintf("%d ", v)))
	}
	buf.Write([]byte(fmt.Sprintf("%d\n", list[n-1])))
	buf.Flush()
}

func max(a, b int) int {
	if a > b {
		return a
	} else {
		return b
	}
}

func min(a, b int) int {
	if a > b {
		return b
	} else {
		return a
	}
}

//solve

const MAX = 100
const WHITE = 0
const GRAY = 1
const BLACK = 2

var time, n int

//隣接行列
var M [MAX][MAX]int

//d[i]: 最初にiを訪問した時刻。発見時刻
//f[i]: iの隣接リストを訪問し終えた時刻。完了時刻
var color, d, f [MAX]int

func dfs_visit(u int) {
	color[u] = GRAY
	time++
	d[u] = time
	//隣接を調べる
	for v := 0; v < n; v++ {
		if M[u][v] == 0 {
			continue
		}
		//隣接するvが、未訪問だった場合
		if color[v] == WHITE {
			dfs_visit(v)
		}
	}
	//訪問完了処理
	color[u] = BLACK
	time++
	f[u] = time
	//訪問完了
}

func dfs() {
	//初期化
	for u := 0; u < n; u++ {
		color[u] = WHITE
	}
	time = 0

	//未訪問のuを始点として、深さ優先探索
	for u := 0; u < n; u++ {

		if color[u] == WHITE {
			dfs_visit(u)
		}
	}

	for u := 0; u < n; u++ {
		fmt.Println(u+1, d[u], f[u])
	}
}

func main() {
	sc.Split(bufio.ScanWords)
	n = nextInt()
	for i := 0; i < n; i++ {
		u, k := nextInt(), nextInt()
		M[u-1][u-1] = 0

		//fmt.Println(u, k)
		if k > 0 {
			for j := 0; j < k; j++ {

				v := nextInt()
				M[u-1][v-1] = 1

			}
		}

	}

	dfs()

}

C++: #define _USE_MATH_DEFINES
#include <algorithm>
#include <bitset>
#include <cassert>
#include <cctype>
#include <clocale>
#include <cmath>
#include <cstdlib>
#include <ctime>
#include <functional>
#include <iomanip>
#include <iostream>
#include <list>
#include <map>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <tuple>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>

using namespace std;

#define IOS ios::sync_with_stdio(false); cin.tie(0);
#define FOR(i, s, n) for(int i = (s), i##_len=(n); i < i##_len; ++i)
#define FORS(i, s, n) for(int i = (s), i##_len=(n); i <= i##_len; ++i)
#define VFOR(i, s, n) for(int i = (s); i < (n); ++i)
#define VFORS(i, s, n) for(int i = (s); i <= (n); ++i)
#define REP(i, n) FOR(i, 0, n)
#define REPS(i, n) FORS(i, 0, n)
#define VREP(i, n) VFOR(i, 0, n)
#define VREPS(i, n) VFORS(i, 0, n)
#define RFOR(i, s, n) for(int i = (s), i##_len=(n); i >= i##_len; --i)
#define RFORS(i, s, n) for(int i = (s), i##_len=(n); i > i##_len; --i)
#define RREP(i, n) RFOR(i, n, 0)
#define RREPS(i, n) RFORS(i, n, 0)
#define ALL(v) (v).begin(), (v).end()
#define SORT(v) sort(ALL(v))
#define RSORT(v) sort(ALL(v), greater<decltype(v[0])>())
#define SZ(x) ((int)(x).size())
#define PB push_back
#define MP make_pair
#define MT make_tuple
#define BIT(n) (1LL<<(n))
#define UNIQUE(v) v.erase(unique(ALL(v)), v.end())

using ll = long long;
using Pi_i = pair<int, int>;
using VB = vector<bool>;
using VC = vector<char>;
using VD = vector<double>;
using VI = vector<int>;
using VLL = vector<ll>;
using VS = vector<string>;
using VSH = vector<short>;

const int MOD = 1000000007;
const int INF = 1000000000;
const int NIL = -1;

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



VI visitedTime, allSearchedTime;
vector<VI> edge;
int n, t;

void dfs(int u){
    visitedTime[u] = ++t;
    for(auto v: edge[u]){
        if(!visitedTime[v]) dfs(v);
    }
    allSearchedTime[u] = ++t;
}

void solve(){
    t = 0;
    REP(u, n)
        if(!visitedTime[u]) dfs(u);
    
    REP(u, n)
        cout << u+1 << " " << visitedTime[u] << " " << allSearchedTime[u] << "\n";
}

int main(){
    cin >> n;
    visitedTime.resize(n, 0);
    allSearchedTime.resize(n, 0);
    edge.resize(n);
    REP(i, n){
        int u; cin >> u; --u;
        int k; cin >> k;
        REP(j, k){
            int v; cin >> v; --v;
            edge[u].PB(v);
        }
    }

    solve();
    return 0;
}

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

int a[100][100],n;
int d[100],f[100],c[100],tt;
int nt[100];

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

void dfs_v(int r){
  for(int i=0;i<n;i++) nt[i]=0;
  stack<int> s;
  s.push(r);
  c[r]=1;
  d[r]=++tt;
  while(!s.empty()){
    int u=s.top();
    int v=next(u);
    if(v!=-1){
      if(c[v]==0){
	c[v]=1;
	d[v]=++tt;
	s.push(v);
      }
    }else{
      s.pop();
      c[u]=2;
      f[u]=++tt;
    }
  }
}

void dfs(){
  for(int i=0;i<n;i++){
    c[i]=0;
    nt[i]=0;
  }
  tt=0;
  for(int i=0;i<n;i++){
    if(c[i]==0) dfs_v(i);
  }
  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++) a[i][j]=0;
  }
  for(int i=0;i<n;i++){
    cin>>u>>k;
    u--;
    for(int j=0;j<k;j++){
      cin>>v;
      v--;
      a[u][v]=1;
    }
  }
  dfs();
  return 0;
}

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

using namespace std;

int N,k[1000];
int v[1000][1000];
int found[1000] = {0},ended[1000] = {0};
int keep;
int checking=0;

void dfs(int cur);

int main() {
	cin >> N;
	for(int i=1;i<N+1;i++) {
		cin >> keep >> k[i];
		for(int j=1;j<k[i]+1;j++) {
			cin >> v[i][j];

		}
	}
	dfs(1);
	while(true) {
		//cout << "processing..." << endl;
		bool flag = false;
		int key = 1;
		for(int i=1;i<N+1;i++) {
			if(found[i] == 0) {
				flag = true;
				key = i;
				break;
			}
		}
		if(flag) {
			dfs(key);
		} else {
			break;
		}
	}
	
	
	for(int i=1;i<N+1;i++) {
		cout << i << " " << found[i] << " " << ended[i] << endl;
	}
	

}

void dfs(int cur) {
	bool REkirrer = false;
	for(int i=1;i<N+1;i++) {
		if(found[i] == 0) {
			REkirrer = true;
		}
	}
	if(!REkirrer) return;
	int loopcount=0;
	//cout << "process ended" << endl;
	if(!found[cur]) {
		checking++;
		//cerr << "visiting: " << cur << " " << "time: " << checking << endl;
		found[cur] = checking;

	}
	for(int dst=1;dst<N+1;dst++) {
		loopcount++;
		bool flag = false;
		for(int i=1;i<k[cur]+1;i++) {
			if(v[cur][i] == dst) flag = true;
		}
		if((flag) && (dst != cur)) dfs(dst);
	}
	if(!ended[cur]) {
		checking++;
		//cerr << "ended: " << cur << " " << "time: " << checking << endl;
		ended[cur] = checking;
	}
}

C++: #include <iostream>
#include <cstdio>
#include <vector>
#include <stack>
#include <string>
#include <queue>

using namespace std;

int d[101];
int f[101];
bool isUsed[101];
int time = 0;

void DFS(vector< vector<int> >& G, int vertex)
{
	d[vertex] = ++time;
	for (int i = 0; i < G[vertex].size(); ++i)
	{
		if (G[vertex][i] == 1 && isUsed[i] == false)
		{
			isUsed[i] = true;
			DFS(G, i);
		}
	}
	f[vertex] = ++time;
}

void solve()
{
	int n;
	cin >> n;
	vector< vector<int> > G(n, vector<int>(n));
	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;
		}
	}
	for (int i = 0; i < 101; ++i)
	{
		isUsed[i] = false;
	}
	isUsed[0] = true;
	DFS(G, 0);
	for (int i = 0; i < n; ++i)
	{
		cout << i + 1 << " " << d[i] << " " << f[i] << endl;
	}
}

int main()
{
	solve();
	return(0);
}