Go: package main

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

func getScanner(fp *os.File) *bufio.Scanner {
	scanner := bufio.NewScanner(fp)
	scanner.Split(bufio.ScanWords)
	scanner.Buffer(make([]byte, 1000005), 1000005)
	return scanner
}

func getNextString(scanner *bufio.Scanner) string {
	scanner.Scan()
	return scanner.Text()
}

func getNextInt(scanner *bufio.Scanner) int {
	i, _ := strconv.Atoi(getNextString(scanner))
	return i
}

func getNextInt64(scanner *bufio.Scanner) int64 {
	i, _ := strconv.ParseInt(getNextString(scanner), 10, 64)
	return i
}

func getNextUint64(scanner *bufio.Scanner) uint64 {
	i, _ := strconv.ParseUint(getNextString(scanner), 10, 64)
	return i
}

func getNextFloat64(scanner *bufio.Scanner) float64 {
	i, _ := strconv.ParseFloat(getNextString(scanner), 64)
	return i
}

func main() {
	fp := os.Stdin
	wfp := os.Stdout
	cnt := 0

	if os.Getenv("MASPY") == "ますピ" {
		fp, _ = os.Open(os.Getenv("BEET_THE_HARMONY_OF_PERFECT"))
		cnt = 1
	}
	if os.Getenv("MASPYPY") == "ますピッピ" {
		wfp, _ = os.Create(os.Getenv("NGTKANA_IS_GENIUS10"))
	}

	scanner := getScanner(fp)
	writer := bufio.NewWriter(wfp)
	solve(scanner, writer)
	for i := 0; i < cnt; i++ {
		fmt.Fprintln(writer, "-----------------------------------")
		solve(scanner, writer)
	}
	writer.Flush()
}

func solve(scanner *bufio.Scanner, writer *bufio.Writer) {
	n := getNextInt(scanner)
	g := graph{}
	g.ee = make([]Edges, n)
	g.visited = make([]bool, n)
	g.found = make([]int, n)
	g.leave = make([]int, n)
	for i := 0; i < n; i++ {
		u := getNextInt(scanner) - 1
		k := getNextInt(scanner)
		for j := 0; j < k; j++ {
			v := getNextInt(scanner) - 1
			g.ee[u] = append(g.ee[u], Edge{
				to: v,
				id: u,
			})
		}
	}
	for i := 0; i < n; i++ {
		sort.Sort(g.ee[i])
	}
	for i := 0; i < n; i++ {
		if g.visited[i] {
			continue
		}
		g.dfs(i)
	}

	for i := 0; i < n; i++ {
		fmt.Fprintln(writer, fmt.Sprintf("%d %d %d", i+1, g.found[i], g.leave[i]))
	}
}

// Edge ...
type Edge struct {
	to, id int
}

type Edges []Edge

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

type graph struct {
	ee           []Edges
	t            int
	n            int
	visited      []bool
	found, leave []int
}

func (g *graph) dfs(i int) {
	g.visited[i] = true
	g.t++
	g.found[i] = g.t
	for _, e := range g.ee[i] {
		if g.visited[e.to] {
			continue
		}
		g.dfs(e.to)
	}
	g.t++
	g.leave[i] = g.t
}

C++: #include <bits/stdc++.h>
using namespace std;
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define rep(i,n)   for(int i=0;i<(n);++i)
#define SORT(c)    sort((c).begin(),(c).end())
#define CLR(a)     memset((&a), 0 ,sizeof(a))//clear memory
#define dump(x)    cerr << #x << " = " << (x) << endl;//debug
#define debug(x)   cerr << #x << " = " << (x) << " (L" << __LINE__ << ")" << " " << __FILE__ << endl;
#define EPS        1e-10//sample:if((double)>=(double)+EPS)
//cin,cout release
//std::cin.tie(0);
//ios::sync_with_stdio(false);

using namespace std;
int n,v[100+1][100+1]={},color[100+1]={},tim,d[1000],f[1000];
void visit(int u){
  color[u]=1;
  d[u]=++tim;
  rep(i,n){
    if(v[u][i]==0)continue;
    if(color[i]==0)
      visit(i);
  }
  color[u]=2;
  f[u]=++tim;
}
void dfs(){
  rep(i,n)color[i]=0;
  tim = 0;
  rep(i,n){
    if(color[i]==0)
      visit(i);
  }
}

int main(){
  cin>>n;
  int u,k,in;
  rep(i,n){
    cin>>u>>k;
    rep(j,k){
      cin>>in;
      v[u-1][in-1]=1;
    }
  }
  dfs();
  rep(i,n)cout<<i+1<<" "<<d[i]<<" "<<f[i]<<endl;
  return 0;
}

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

#define N 100
#define WHITE 0
#define GRAY 1
#define BLACK 2

stack<int> S;
int n, M[N][N];
int color[N], d[N], f[N], tt;
int nt[N]; //未訪問な次の頂点を保持

//未訪問な次の頂点を返す．全て訪問済みなら-1を返す
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 i){
    S.push(i);
    color[i] = GRAY;
    d[i] = ++tt;

    while(!S.empty()){
        int u = S.top();
        int v = next(u);
        if(v != -1){
            if(color[v] == WHITE){
                S.push(v);
                color[v] = GRAY;
                d[v] = ++tt;
            }
        }else{
            color[u] = BLACK;
            f[u] = ++tt;
            S.pop();
        }
    }
}

void dfs(){
    for(int i = 0; i < n; i++){
        color[i] = WHITE;
        nt[i] = 0;
    }
    tt = 0;

    for(int i = 0; i < n; i++){
        if(color[i] == WHITE) dfs_visit(i);
    }

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

}

int main(){
    int u, k, v;
    cin >> n;
    //隣接行列の作製
    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--; //0オリジンに変換
        for(int j = 0; j < k; j++){
            cin >> v;
            v--; //0オリジンに変換
            M[u][v] = 1;
        }
    }

    dfs();
    
    return 0;

}

C++: //Shunji Lin 08-144505

#include <iostream>

using namespace std;

bool adjmatrix[101][101]; //adjmatrix
int discover[101];
int processed[101];
int cur_time = 0;


void DFS(int vertex, int N) {
  cur_time++;
  discover[vertex] = cur_time; // set cost
  
  for (int i =1; i<= N; i++) {
    if(adjmatrix[vertex][i] && discover[i] == -1) {
      DFS(i, N);
    }
  }
  
  cur_time++;
  processed[vertex] = cur_time;
}


  
int main() {
  const int cur_time = 0;
  
  for (int i = 0; i < 101; i++) {
    discover[i] = -1; // upper limit
    processed[i] = -1;
  }
  int N;
  cin >> N;

  for (int i = 1; i <= N; i++) {
    int vertex, degree;
    cin >> vertex >> degree;

    for (int j = 0; j < degree; j++) {
      int outvertex;
      cin >> outvertex;
      adjmatrix[i][outvertex] = true;
    }
  }

  
  

  DFS(1,N);


  for (int i = 1; i <=N; i++) {
    if (discover[i] != -1) {
      cout << i << " " << discover[i] << " "<< processed[i] << endl;
    }
  }
}

C++: #include <iostream>
#include <algorithm>
#include <string>
#include <vector>
#include <cstdio>
#include <cmath>
#include <cstdlib>
#include <cstring>
#include <stack>
#include <queue>
#include <set>
#include <map>
#include <list>
#include <utility>
#include <ctime>
#define INF 1000000000
#define LINF 9000000000000000000
#define mod 1000000007
 
#define rep(i,n) for(int i=0;i<int(n);i++)
#define rrep(i,n) for(int i=(n);i>=0;i--)
#define REP(i,a,b) for(int i=(a);i<int(b);i++)
#define all(x) (x).begin(),x.end()
#define vector_rsort(x) sort(all(x));reverse(all(x))
#define array_rsort(x,n) sort(x,x+n);reverse(x,x+n);
#define pb push_back
#define mp make_pair
#define MOD(x) (x%(mod))

#define Yes cout<<"Yes"<<endl
#define YES cout<<"YES"<<endl
#define No cout<<"No"<<endl
#define NO cout<<"NO"<<endl
using namespace std;
 
typedef long long ll;
typedef unsigned long long ull;
typedef vector<int> vi;
typedef pair<int,int> pi;
 
int dx[4]={1,0,-1,0};
int dy[4]={0,1,0,-1};
bool debug=false;
/*---------------------------------------------------*/

int n,t=1;
int d[105],f[105];
int used[105];
vi g[105];

void init(){
  rep(i,105){
    d[i]=f[i]=INF;
  }
}

void dfs(int now){
  d[now]=min(d[now],t);
  rep(i,g[now].size()){
    if(!used[g[now][i]]){
      used[g[now][i]]=true;
      t++;
      dfs(g[now][i]);
    }
  }
  t++;
  f[now]=min(f[now],t);
}

int main(){
  int u,k,v;
  cin>>n;
  rep(i,n){
    cin>>u>>k;
    rep(j,k){
      cin>>v;
      g[u].pb(v);
    }
  }
  init();
  dfs(1);
  REP(i,1,n+1){
    cout<<i<<" "<<d[i]<<" "<<f[i]<<endl;
  }
  return 0;
}