Go: package main

/*
深さ優先探索
*/

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

func main() {
	scanner := makeScanner(8192)
	n := eGetInt(scanner)
	g := make([][]int, n+1)
	for i := 1; i < n+1; i++ {
		ints := eGetInts(scanner)
		num, vcount := ints[0], ints[1]
		g[i] = make([]int, vcount)
		for j := 0; j < vcount; j++ {
			g[num][j] = ints[j+2]
		}
	}
	hist := make([]struct{ d, f int }, n+1)
	t := 0
	var visit func(int)
	visit = func(num int) {
		if hist[num].d == 0 {
			stack := []int{}
			t++
			hist[num].d = t
			stack = append(stack, num)
			for len(stack) > 0 {
				// トップを訪問する
				top := stack[len(stack)-1]
				for i := 0; i < len(g[top]); i++ {
					if hist[g[top][i]].d == 0 {
						t++
						hist[g[top][i]].d = t
						stack = append(stack, g[top][i])
						goto endloop
					}
				}
				// 訪問場所がなくなったら
				// pop
				stack = stack[0 : len(stack)-1]
				t++
				hist[top].f = t
			endloop:
			}
		}
	}
	for i := 1; i < n+1; i++ {
		visit(i)
	}
	for i := 1; i < n+1; i++ {
		fmt.Println(i, hist[i].d, hist[i].f)
	}
}

////////////////////////////////////////////////////////////////////////////////
// ライブラリ
////////////////////////////////////////////////////////////////////////////////
func makeScanner(maxByte int) *bufio.Scanner {
	scanner := bufio.NewScanner(os.Stdin)
	scanner.Buffer(make([]uint8, 0, 8192), maxByte)
	return scanner
}
func makeWordScanner() *bufio.Scanner {
	scanner := makeScanner(8192)
	scanner.Split(bufio.ScanWords)
	return scanner
}
func eGetLine(r *bufio.Scanner) string {
	if r.Scan() {
		return r.Text()
	}
	err := r.Err()
	if err != nil {
		log.Fatal(err)
	}
	// EOF
	return ""
}
func eGetInt(r *bufio.Scanner) int {
	line := eGetLine(r)
	return eAtoi(line)
}
func eGetInt64(r *bufio.Scanner) int64 {
	line := eGetLine(r)
	return eAtoInt64(line)
}
func eGetFields(r *bufio.Scanner) []string {
	line := eGetLine(r)
	return strings.Fields(line)
}
func eGetInts(r *bufio.Scanner) []int {
	fields := eGetFields(r)
	ints := make([]int, len(fields))
	for i := 0; i < len(ints); i++ {
		ints[i] = eAtoi(fields[i])
	}
	return ints
}
func eGetInt64s(r *bufio.Scanner) []int64 {
	fields := eGetFields(r)
	ints := make([]int64, len(fields))
	for i := 0; i < len(ints); i++ {
		ints[i] = eAtoInt64(fields[i])
	}
	return ints
}
func eGetChars(r *bufio.Scanner) []string {
	line := eGetLine(r)
	return strings.Split(line, "")
}
func eAtoi(s string) int {
	n, err := strconv.Atoi(s)
	if err != nil {
		log.Fatal(err)
	}
	return n
}
func eAtoInt64(s string) int64 {
	n, err := strconv.ParseInt(s, 10, 64)
	if err != nil {
		log.Fatal(err)
	}
	return n
}

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>
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, tt;
int color[N], nt[N], M[N][N], d[N], f[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 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;
	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 <stdio.h>
#define MAX 101
 
int n, ni = 1;
int A[MAX][MAX] = {0}, a[MAX] = {0}, b[MAX] = {0};
 
void serch(int x){
  int i;
   
  a[x] = ni++;
  for(i=1; i<=n; i++){
    if(a[i] == 0 && A[x][i] == 1)
      serch(i);
  }
  b[x] = ni++;
}
 
int main(){
  int i, j, k, x, y;
   
  scanf("%d", &n);
  for(i=1; i<=n; i++){
    scanf("%d%d", &x, &k);
    for(j=1; j<=k; j++){
      scanf("%d", &y);
      A[x][y] = 1;
    }
  }
  
  for(i=1; i<=n; i++){
    if(a[i] == 0)
      serch(i);
  }
   
  for(i=1; i<=n; i++){
    printf("%d %d %d\n", i, a[i], b[i]);
  }
  
  return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for(int i = 0; i < (int)(n); i++)
#define REP(i, n) for(int i = 1; i <= (int)(n); i++)
const long long INF = 1LL << 60;
const double PI=3.14159265358979323846;
#define NIL -1

stack<int>S;
int A[1000][1000]={};
string color[1000]={"WHITE"};
int d[1000]={},f[1000]={},nt[1000];
int n,tt=0;

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


void dfs(int u){
    S.push(u);
    color[u]="GRAY";
    d[u] = ++tt;

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

}

    void dfs_init(){
        REP(i,n){
            color[i]="WHITE";
            nt[i]=0;
        }
    }

int main() 
{
    cin >> n;

    int p,k;
    rep(i,n){
        cin >> p >> k;
        int q;
            rep(j,k){
                cin >> q;
                A[p][q] = 1;
            }
    }

    dfs_init();
    for(int i=1;i<=n;i++){
        if(color[i] == "WHITE")dfs(i);
    }

    REP(i,n){
        cout << i <<" " << d[i] << " " << f[i] << endl;
    }

}