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 <vector>
#include <iostream>
#include <set>
#include <cstdio>
#include <queue>
#include <cstdio>
#include <cstdlib>
#include <cassert>
#include <ctime>
#include <cmath>
#include <complex>
#include <algorithm>
#include <tuple>
#include <algorithm>
#include <limits>
#include <map>

using namespace std;

typedef long long ll;
typedef pair<int, int> P;
typedef tuple<int, int, int> T;

int d[110], f[110];
vector<int> g[110];
int t;
bool used[110];
void solve(int i, int b) {
    if (used[i]) return;
    used[i] = true;
    t++;
    d[i] = t;
    for (int j: g[i]) {
        if (j == b) continue;
        solve(j, i);
    }
    t++;
    f[i] = t;
}

int main() {
    int n;
    cin >> n;
    for (int i = 0; i < n; i++) {
        int id, u;
        cin >> id >> u;
        for (int j = 0; j < u; j++) {
            int a;
            cin >> a;
            g[i].push_back(a-1);
        }
    }
    t = 0;
    fill_n(used, 110, false);
    solve(0, -1);
    for (int i = 0; i < n; i++) {
        printf("%d %d %d\n", i+1, d[i], f[i]);
    }
    return 0;
}