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

// u に隣接する v を番号順に取得
int next(int u) {
  for ( int v = nt[u]; v < n; v++ ) {
    nt[u] = v + 1;
    if ( M[u][v] ) return v;
  }
  return -1;
}

// スタックを用いた深さ優先探索
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() {
  // 初期化
  for ( int i = 0; i < n; i++ ) {
    color[i] = WHITE;
    nt[i] = 0;
  }
  tt = 0;

  // 未訪問の u を始点として深さ優先探索
  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 <iostream>
#include <string>
#include <stdio.h>
using namespace std;

int d[100];
int f[100];
int map[100][100];
int time=0;
int n;
void visit(int);

int main(){
	int i,j,k,u,v;
	for(i=0;i<100;i++) d[i]=-1;
	for(i=0;i<100;i++) f[i]=-1;
	cin >> n;
	for(i=0;i<n;i++){
		for(j=0;j<n;j++){
			map[i][j]=0;
		}
	}
	for(i=0;i<n;i++){
		cin>>u>>k;
		for(j=0;j<k;j++){
			cin>>v;
			map[u-1][v-1]=1;
		}
	}
	visit(0);
	// ??¨???????????????????????????????????°?¨????????????¨??????
	for(i=0;i<n;i++){
		cout<< i+1 << " "<<d[i]<< " "<<f[i];
		cout<<endl;
	}
	return 0;
}

void visit(int k){
	int i;
	d[k]=++time;
	for(i=0;i<n && f[k]==-1;i++){
		if(map[k][i]==1&&d[i]==-1){
			visit(i);
		}
	}
	f[k]=++time;
}

C++: #include <bits/stdc++.h>
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define rep1(i, n) for (int i = 1; i < (n); ++i)
using namespace std;
typedef long long ll;

vector<vector<int>> g;
vector<bool> seen;
vector<int> found;

void dfs(int v){
    seen[v] = true;
    found.push_back(v);

    if(g[v].size()==0){
        return;
    }

    for(int nv: g[v]){
        if(!seen[nv]){
            dfs(nv);
            found.push_back(nv);
        }
    }
}

int main() {
    cin.tie(nullptr);
    ios::sync_with_stdio(false);

    int n;
    cin >> n;

    g.resize(n);
    seen.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);
        }
    }

    rep(i, n){
        if(!seen[i]) {
            dfs(i);
            found.push_back(i);
        }
    }
    
    vector<vector<int>> res(n, vector<int>(2, -1));
    rep(i, n){
        rep(j, found.size()){
            if(found[j]==i && res[i][0]==-1) res[i][0] = j+1;
            if(found[j]==i && res[i][0]!=-1) res[i][1] = j+1;
        }
    }

    rep(i, n) cout << i+1 << " " << res[i][0] << " " << res[i][1] << endl;

    return 0;
}

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 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 <iostream>
#include <stack>
#include <vector>

using namespace std;

int n;
int G[105][105];
vector<int> d(105,0),f(105,0);
int t=0;

void dfs(int x){
    bool p = false;
    if(d[x]!=0) p = true;
    if(d[x]==0){
        t++;
        d[x]=t;
    }
    for (int j=1; j<=n; j++) {
        if (G[x-1][j-1]==1 and d[j]==0) {
            dfs(j);
        }
    }
    t++;
    if(p) t--;
    if(f[x]==0) f[x]=t;
}


int main(){
    cin >> n;
    for (int i =0; i<n; i++) {
        for (int j =0; j<n; j++) {
            G[i][j] = 0;
        }
    }
    for (int i=0;i<n;i++) {
        int p,m;
        cin >>p >> m;
        for (int j=0; j<m; j++) {
            int q;
            cin >> q;
            G[p-1][q-1]=1;
        }
    }
    for(int i=0;i<n;i++) {
        dfs(i+1);
    }
    for (int i=0; i<n; i++) {
        cout << i+1 << " "<<d[i+1]<<" "<<f[i+1]<<endl;
    }
}