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>
#define MAX 101
#define NIL -1

using namespace std;


int matrix[MAX][MAX] = {0};
int d[MAX], f[MAX];
int n, t;

void dfs();
void dfs_visit(int u);
int next(int u);

int main()
{
	cin >> n;
	
	for (int i = 0; i < n; i++)
	{
		int u, k, v;
		cin >> u >> k;
		for (int j = 0; j < k; j++)
		{
			cin >> v;
			matrix[u][v] = 1;			
		}
	}
	
//显示邻接矩阵 
//	for (int i = 0; i < n; i++)
//	{
//		for (int j = 0; j < n; j++)
//		{
//			if(j) cout << ' ';
//			cout << matrix[i+1][j+1];		
//		}
//		cout << endl;
//	}
	
	
	dfs();
	
	
	for (int i = 1; i <= n; i++)
	{
		cout << i << ' ';
		cout << d[i] << ' ';	
		cout << f[i] << endl;
	}
} 



void dfs()
{	
	for (int i = 1; i <= n; i++)
	{
		if (d[i] == 0)
			dfs_visit(i);
	}
}



void dfs_visit(int u)
{

	stack<int> S;
	S.push(u);
	d[u] = ++t;
	
	while (!S.empty())
	{
		u = next(S.top());
		if (u)
		{
//			if (d[u] == 0)
			{
			d[u] = ++t;
			S.push(u); 				
			}
		}
		else
		{
			f[S.top()] = ++t;
			S.pop();
		}
		
	}
	
}


int next(int u)
{
	for (int i = 1; i <= n; i++)
	{
		if (matrix[u][i] != 0 && d[i] == 0)
			return i;
	}
	return 0;
}

C++: #include <iostream>
#include <list>
#include <vector>

struct TNode
{
	int Index;
	bool Visited;
	std::list<TNode*> Target;
	
	int ClockStart;
	int ClockEnd;
	
	TNode(int AIndex)
	: Index(AIndex), Visited(false), ClockStart(0), ClockEnd(0)
	{
	}
	
	void Visit(int& Clock)
	{
		if(Visited) return;
		Visited = true;
		ClockStart = Clock;
		++Clock;
		for(std::list<TNode*>::iterator It = Target.begin(); It != Target.end(); ++It){
			(*It)->Visit(Clock);
		}
		ClockEnd = Clock;
		++Clock;
	}
};

class TGraph
{
	std::vector<TNode*> FNodes;
public:
	TGraph(int Count)
	: FNodes(Count)
	{
		for(int i = 0; i < Count; ++i){
			FNodes[i] = new TNode(i + 1);
		}
	}
	
	~TGraph()
	{
		for(unsigned int i = 0; i < FNodes.size(); ++i){
			delete FNodes[i];
		}
	}
	
	void InputNode(int Index, int BranchCount)
	{
		for(int i = 0; i < BranchCount; ++i){
			int Target;
			std::cin >> Target;
			FNodes[Index - 1]->Target.push_back(FNodes[Target - 1]);
		}
	}
	
	void DepthFirstSearch()
	{
		int Clock = 1;
		for(unsigned int i = 0; i < FNodes.size(); ++i){
			FNodes[i]->Visit(Clock);
		}
	}
	
	void OutputClocks()const
	{
		for(unsigned int i = 0; i < FNodes.size(); ++i){
			std::cout << FNodes[i]->Index      << " "
			          << FNodes[i]->ClockStart << " "
			          << FNodes[i]->ClockEnd   << std::endl;
		}
	}
};

int main()
{
	int Count;
	std::cin >> Count;
	TGraph Graph(Count);
	for(int i = 0; i < Count; ++i){
		int Index;
		std::cin >> Index;
		int BranchCount;
		std::cin >> BranchCount;
		Graph.InputNode(Index, BranchCount);
	}
	Graph.DepthFirstSearch();
	Graph.OutputClocks();
	return 0;
}