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 <bits/stdc++.h>
using namespace std;
#define REP(i, s, n) for (int i = s; i < n; ++i)
#define rep(i, n) REP(i, 0, n)
#define SORT(c) sort((c).begin(), (c).end())
#define IINF INT_MAX
#define LLINF LLONG_MAX
#define DEBUG true
// sort(a.begin(), a.end(), std::greater<int>());

/*
std::vector<std::string> split(const std::string &input, char delimiter)
{
    std::istringstream stream(input);

    std::string field;
    std::vector<std::string> result;
    while (std::getline(stream, field, delimiter))
    {
        result.push_back(field);
    }
    return result;
}
*/
vector<int> data[100];
pair<int, int> finds[100];

int dfs(int foo, int timer)
{
    //foo is node number
    if (finds[foo].first != -1)
        return timer;
    finds[foo].first = ++timer;
    int result = timer;
    if (data[foo].size() != 0)
    {
        rep(i, data[foo].size())
        {
            result = dfs(data[foo][i], result);
        }
    }
    finds[foo].second = ++result;
    return result;
}

int main()
{
    int n;
    cin >> n;
    rep(i, n)
    {
        int temp;
        cin >> temp;
        cin >> temp;
        rep(j, temp)
        {
            int foo;
            cin >> foo;
            data[i].push_back(foo - 1);
        }
    }
    rep(i, 100)
    {
        finds[i].first = -1;
    }
    int hoge = 0;
    rep(i, n) if (finds[i].first == -1)
        hoge = finds[i].second = dfs(i, hoge);
    rep(i, n)
    {
        cout << i + 1 << " " << finds[i].first << " " << finds[i].second << 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, tt;
int M[N][N], color[N], d[N], f[N], 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 {
		   color[u] = BLACK;
		   S.pop();
		   f[u] = ++tt;
		}
	} 
}


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

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

int main() {
	int k , u, 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 i = 0; i < k; i++) {
	        cin >> v;
	        v--;
		   M[u][v] = 1; 
     	}
	} 
	
	dfs();
	
	return 0;
}

C++: #include<cstdio>
#define WHITE 0
#define GRAY  1
#define BLACK 2
#define MAX 100

void InitializeBoolMatrix(int nmbr_of_rows, int nmbr_of_columns, bool mtrx[][MAX]){
	for (int row = 0; row < nmbr_of_rows; ++row) {
		for (int column = 0; column < nmbr_of_columns; ++column)
			mtrx[row][column] = false;
	}
}

void ListToMatrix(int number_of_vertices, bool mtrx[][MAX]){
	int vertex_from, vertex_to, degree_out;	
	for (int vertex_i = 0; vertex_i < number_of_vertices; ++vertex_i) {
		scanf("%d %d", &vertex_from, &degree_out);
		vertex_from--; //0?????????????????????
		for (int vertex_out_i = 0; vertex_out_i < degree_out; ++vertex_out_i) {
			scanf("%d", &vertex_to);
			vertex_to--; //0?????????????????????
			mtrx[vertex_from][vertex_to] = true;
		}
	}
}

void BuildAdjacencyMatrix(int n, bool adjmtrx[][MAX]){
	InitializeBoolMatrix(n, n, adjmtrx);
	ListToMatrix(n, adjmtrx);
}

bool adjmtrx[MAX][MAX];
bool has_not_been_discovered_yet[MAX];
int time;
int discoveredtime[MAX];
int finishedtime[MAX];

void Dfs(int present_vertex, int n){
	int pv = present_vertex;
	has_not_been_discovered_yet[pv] = false;
	discoveredtime[pv] = ++time;
	for(int v = 0;v < n;v++){
		if(adjmtrx[pv][v] && has_not_been_discovered_yet[v]){
			Dfs(v, n);
		}
	}
	finishedtime[pv] = ++time;
}

void DfsInit(int n){
	for (int i = 0; i < n; ++i)
		has_not_been_discovered_yet[i] = true;
	time = 0;
}

int main(){
	int number_of_vertices;
	scanf("%d", &number_of_vertices);
	int n = number_of_vertices;
	BuildAdjacencyMatrix(n, adjmtrx);
	DfsInit(n);
	for (int vertex_i = 0; vertex_i < n; ++vertex_i){
		if(has_not_been_discovered_yet[vertex_i])
			Dfs(vertex_i, n);
	}
	for (int id = 0; id < n; ++id)
		printf("%d %d %d\n", id+1, discoveredtime[id], finishedtime[id]);
	return 0;
}

C++: /* 
 * ALDS1_11B.cpp
 */
#include <iostream>
#include <vector>
#include <cstdio>
#include <cstdlib>
#include <cstring>

using namespace std;

int N;
int ad_k[101];
int ad_list[101][101];

int time = 0;
int d[101], f[101];
bool visited[101];

void visit(int id) {
    if (visited[id])
        return;

    visited[id] = true;
    d[id] = ++time;
    for (int i = 0; i < ad_k[id]; ++i) {
        visit(ad_list[id][i]);
    }
    f[id] = ++time;
}

int main(void) {

    scanf("%d", &N);
    for (int i = 1, id; i <= N; ++i) {
        scanf("%d %d", &id, ad_k + i);
        for (int j = 0; j < ad_k[id]; ++j) {
            scanf("%d", ad_list[id] + j);
        }
    }

    visit(1);

    for (int i = 1; i <= N; ++i) {
        printf("%d %d %d\n", i, d[i], f[i]);
    }

    return 0;
}