Go: package main

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

func main() {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)
	sc.Scan()
	num, _ := strconv.Atoi(sc.Text())
	nodes := make(map[int]*node)

	for i := 0; i < num; i++ {
		sc.Scan()
		id, _ := strconv.Atoi(sc.Text())
		sc.Scan()
		nodeNum, _ := strconv.Atoi(sc.Text())
		n := node{id, make([]int, 0), 0, 0}
		for j := 0; j < nodeNum; j++ {
			sc.Scan()
			nid, _ := strconv.Atoi(sc.Text())
			n.nexts = append(n.nexts, nid)
		}
		nodes[id] = &n
	}

	s := Stack{}
	for i := 1; i < len(nodes)+1; i++ {
		if nodes[i].s != 0 {
			continue
		}
		walk(i, &nodes, s)
	}
	for i := 1; i < len(nodes)+1; i++ {
		fmt.Printf("%v %v %v\n", (*nodes[i]).id, (*nodes[i]).s, (*nodes[i]).e)
	}
}

var time int

func walk(nid int, nodes *map[int]*node, s Stack) {
	n := (*nodes)[nid]
	if n.s != 0 {
		return
	}
	time++
	n.s = time
	s.Push(n)
	for _, v := range n.nexts {
		walk(v, nodes, s)
	}
	time++
	n.e = time
}

type node struct {
	id    int
	nexts []int
	s     int
	e     int
}

// Stack is Stack
type Stack struct {
	stack []interface{}
}

// Push new value
func (stack *Stack) Push(val interface{}) {
	stack.stack = append(stack.stack, val)
}

// Pop new value
func (stack *Stack) Pop() interface{} {
	val := stack.stack[len(stack.stack)-1]
	stack.stack = stack.stack[0 : len(stack.stack)-1]
	return val
}

C++: #include<iostream>
#include<stack> 
const int MAXN = 105;
const int WHITE = 0;
const int GRAY = 1;
const int BLACK = 2;
int a[MAXN][MAXN];
int color[MAXN];
int d[MAXN];
int f[MAXN];
int nt[MAXN];
int n, tt = 0;
using namespace std;

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

void dfs(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_init()
{
	int u;
	for(u = 0; u < n; u++)
	{
		color[u] = WHITE;
		nt[u] = 0;
	}
	tt = 0;
	for(u = 0; u < n; u++)
	{
		if(color[u] == WHITE)
			dfs(u);
	}
	
	for(u = 0; u < n; u++)
	{
		cout << u+1 << " " << d[u] << " " << f[u] << endl;	
	}	
} 

int main ()
{
	int k, u, temp;
	cin >> n;
	for(int i = 0; i < n; i++)
	{
		cin >> u >> k;
		u--;
		for(int j = 0; j < k; j++)
		{
			cin >> temp;
			temp--;
			a[u][temp] = 1;
		}
	}
	dfs_init();
	return 0;
}

C++: #include <iostream>
#include <string>
#include <vector>
#include <functional>
#include <algorithm>
#include <array>
#include <stack>
#include <tuple>

using namespace std;

template<typename ISTREAM>
void readGraphListAsMatrix(const size_t n, ISTREAM& cin, vector< vector<int> >& graphMatrix) {
	graphMatrix = vector< vector<int> >(n, vector<int>(n, 0));
	for (size_t i = 0; i != n; ++i) {
		size_t u;
		size_t k;
		cin >> u;
		cin >> k;
		for (size_t j = 0; j != k; ++j) {
			size_t v;
			cin >> v;
			graphMatrix.at(u - 1).at(v - 1) = 1;
		}
	}
}

void printMatrix(const vector< vector<int> >& graphMatrix) {
	const size_t n = graphMatrix.size();
	for (size_t i = 0; i != n; ++i) {
		const vector<int>& adj = graphMatrix.at(i);
		cout << adj.front();
		for (size_t j = 1; j != n; ++j) {
			cout << " " << adj.at(j);
		}
		cout << endl;
	}
}

template<typename T>
void execute(T& cin) {
	size_t n;
	cin >> n;
	vector< vector<int> > graphMatrix;
	readGraphListAsMatrix(n, cin, graphMatrix);
	stack<size_t> visitedNodeIDs;
	vector<vector<int>::iterator> searchBeginPos;
	searchBeginPos.reserve(n);
	for (auto& v : graphMatrix)searchBeginPos.push_back(v.begin());
	int time = 0;
	vector<pair<int, int>> timeStamp(n,make_pair(0,0));//pair<初回訪問時刻, 完了時刻>
	for (int i = 0; i != n; ++i) {
		pair<int, int>& dp = timeStamp.at(i);
		if (dp.first != 0)continue;
		visitedNodeIDs.push(i);
		dp.first = ++time;
		while (!visitedNodeIDs.empty()) {
			const int nodeID_1 = visitedNodeIDs.top();
			vector<int>& neighbourNodeList = graphMatrix.at(nodeID_1);
			vector<int>::iterator& searchStart = searchBeginPos.at(nodeID_1);
			while (true) {
				searchStart = find(searchStart, neighbourNodeList.end(),1);
				if (searchStart == neighbourNodeList.end()) {
					timeStamp.at(nodeID_1).second = time + 1;
					visitedNodeIDs.pop();
					break;
				}
				else {
					const size_t nextVisitID_1 = distance(neighbourNodeList.begin(), searchStart);
					++searchStart;
					if (timeStamp.at(nextVisitID_1).first == 0) {
						timeStamp.at(nextVisitID_1).first = time + 1;
						visitedNodeIDs.push(nextVisitID_1);
						break;
					}
				}
			}
			++time;
		}
	}
	for (int i = 0; i != n; ++i) {
		cout << i + 1 << " " << timeStamp.at(i).first << " " << timeStamp.at(i).second << endl;
	}
}

int main()
{

	execute(cin);


	return 0;
}