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 <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);
}

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

using namespace std;

#define MAX 110
int num;
int matrix[MAX][MAX];
int dst[MAX];
int counter = 0;
int D[MAX];
int F[MAX];

void input(){
    cin >> num;
    for(int i=0;i<MAX;i++){
        dst[i] = -1;
        for(int j=0;j<MAX;j++){
            matrix[i][j] = 0;
        }
    }
    for(int i=1;i<=num;i++){
        int v; cin >> v;
        int tmp; cin >>tmp;
        for(int j=0;j<tmp;j++){
            int vi; cin >> vi;
            matrix[v-1][vi-1] = 1;
        }
    }
}

void dfs(int cur){
    counter++;
    D[cur] = counter;
    for(int i=0; i< num;i++){
        if(matrix[cur][i] == 1 && D[i]== 0)
            dfs(i);
    }
    F[cur] = counter+1;
    counter++;
    return;
}

int main(){
    input();
    for(int i=0;i<MAX;i++){
        D[i] = 0;
        F[i] = 0;
    }
    dfs(0);
    for(int i=0;i<num;i++){
        cout << i+1 << " " << D[i] << " " << F[i] << endl;
    }
}

C++: #include <iostream>
#include <algorithm>
using namespace std;

int r[101][101];
int d[101], f[101], num, visit[100]={0}, p=1;

void dfs(int n){
    if(visit[n]!=1){
        visit[n] = 1;
        d[n] = p++;
        for(int i=1; i<=num; i++)
            if(r[n][i]) dfs(i);
        f[n] = p++;
    }
}

int main(void){
    int u, k, v;
    cin >> num;
    for(int i=1; i<=num; i++){
        cin >> u >> k;
        for(int j=1; j<=k; j++)
            cin >> v;
            r[u][v]=1;
    }
    for(int i=1; i<=num; i++){
        if(visit[i]!=1) dfs(i);
    }
    for(int i=1; i<=num; i++)
        cout << i << " " << d[i] << " " << f[i] << endl;
    return 0;
}

C++: #include <iostream>
#include <vector>
using namespace  std;

struct StSeq
{
  int m_nBgn;
  int m_nEnd;

  StSeq() : m_nBgn(0), m_nEnd(0)
  { }
};

void fnInput(vector<vector<int>>& rvvnAdjcy, vector<StSeq>& rvoDFSrch)
{
  int nMaxSiz;
  cin >> nMaxSiz;

  rvvnAdjcy.resize(nMaxSiz + 1, vector<int>(nMaxSiz + 1, 0));
  for (int i = 0; i < nMaxSiz; ++i)
  {
    int nx, nSecSiz;
    cin >> nx >> nSecSiz;
    for (int j = 0; j < nSecSiz; ++j)
    {
      int ny;
      cin >> ny;
      rvvnAdjcy[nx][ny] = 1;
    }
  }
  StSeq oSeq;
  rvoDFSrch.resize(nMaxSiz + 1, oSeq);
}

void fnDepthFirstSearch(const vector<vector<int>>& cnrvvnAdjcy, vector<StSeq>& rvoDFSrch, int nx)
{
  static int stnCnt = 0;

  if (rvoDFSrch[nx].m_nBgn)  return;
  rvoDFSrch[nx].m_nBgn = ++stnCnt;

  for (int ny = 1; ny < cnrvvnAdjcy.size(); ++ny)
    if (cnrvvnAdjcy[nx][ny] == 1  &&
        nx != ny               )
      fnDepthFirstSearch(cnrvvnAdjcy, rvoDFSrch, ny);

  rvoDFSrch[nx].m_nEnd = ++stnCnt;
}

void fnResult(const vector<StSeq>& cnrvoDFSrch)
{
  for (int i = 1; i < cnrvoDFSrch.size(); ++i)
    cout << i <<  " " << cnrvoDFSrch[i].m_nBgn << " " << cnrvoDFSrch[i].m_nEnd << endl;
}

int main()
{
  cin.tie(0);
  ios::sync_with_stdio(false);
  vector<vector<int>> vvnAdjcy;
  vector<StSeq> voDFSrch;

  fnInput(vvnAdjcy, voDFSrch);
  for (int nx = 1; nx < voDFSrch.size(); ++nx)
    fnDepthFirstSearch(vvnAdjcy, voDFSrch, nx);
  fnResult(voDFSrch);

  return 0;
}