Go: package main

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

var scanner = bufio.NewScanner(os.Stdin)

func nextString() string {
	scanner.Scan()
	return scanner.Text()
}

func nextInt() int {
	n, err := strconv.Atoi(nextString())
	if err != nil {
		fmt.Printf("strconv.Atoi failed: %v\n", err)
	}
	return n
}

var infty = 1000000000

type nodeKey int

type DirectedGraphNode struct {
	key       nodeKey
	adjacents []*DirectedGraphNode
	visited   bool
	d         int
	f         int
	parent    *DirectedGraphNode
}

type DirectedGraph struct {
	nodes []*DirectedGraphNode
}

func (g *DirectedGraph) setAdjacency(l, r nodeKey) {
	g.nodes[l].adjacents = append(g.nodes[l].adjacents, g.nodes[r])
}

func newDirectedGraph(nNodes int) *DirectedGraph {
	graph := DirectedGraph{}
	graph.nodes = make([]*DirectedGraphNode, nNodes)
	for iNodes := 0; iNodes < nNodes; iNodes++ {
		graph.nodes[iNodes] = &DirectedGraphNode{}
		graph.nodes[iNodes].key = nodeKey(iNodes)

		graph.nodes[iNodes].visited = false
		graph.nodes[iNodes].d = infty
		graph.nodes[iNodes].f = infty
		graph.nodes[iNodes].parent = nil
	}
	return &graph
}

type QueueEntry struct {
	node *DirectedGraphNode
	next *QueueEntry
}

type Queue struct {
	head, tail *QueueEntry
}

func (q *Queue) enqueue(node *DirectedGraphNode) {
	entry := QueueEntry{}
	entry.node = node

	if q.tail == nil {
		q.head = &entry
		q.tail = &entry
		return
	}

	q.tail.next = &entry
	q.tail = q.tail.next
}

func (q *Queue) dequeue() *QueueEntry {
	if q.head == nil {
		return nil
	}
	poped := q.head
	q.head = q.head.next
	if q.head == nil {
		q.tail = nil
	}
	return poped
}

func (q *Queue) isEmpty() bool {
	return q.head == nil
}

var time = 0

func fillDistancesByDepthFirstSearch(g *DirectedGraph) {
	for _, u := range g.nodes[1:] {
		if !u.visited {
			dfsVisit(g, u)
		}
	}
}

func dfsVisit(g *DirectedGraph, u *DirectedGraphNode) {
	time++
	u.d = time

	u.visited = true
	for _, v := range u.adjacents {
		if !v.visited {
			v.parent = u
			dfsVisit(g, v)
		}
	}
	time++
	u.f = time
}

func main() {
	scanner.Split(bufio.ScanWords)

	nNodes := nextInt()
	g := newDirectedGraph(nNodes + 1)

	for iNode := 0; iNode < nNodes; iNode++ {
		nodeKeyLeft := nodeKey(nextInt())
		nAdj := nextInt()
		for iAdj := 0; iAdj < nAdj; iAdj++ {
			nodeKeyRight := nodeKey(nextInt())
			g.setAdjacency(nodeKeyLeft, nodeKeyRight)
		}
	}

	fillDistancesByDepthFirstSearch(g)

	for iNode := 1; iNode <= nNodes; iNode++ {
		node := g.nodes[iNode]
		fmt.Println(node.key, node.d, node.f)
	}
}

C++: #include <iostream>
#include <algorithm>
#include <stack>
#include <queue>
#include <vector>
#include <map>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>

using namespace std;

struct Node {
	int k, d, f;
	vector<int> v;
};

#define MAX_N 100

Node node[MAX_N + 1];
int stamp = 1;;

void dfs(int u) {
	if (node[u].d == 0) node[u].d = stamp++;
	for (int i = 0; i < node[u].k; ++i)
		if (node[u].v[i] != u)
			dfs(node[u].v[i]);
	if (node[u].f == 0) node[u].f = stamp++;
}

int main() {
	int n;
	cin >> n;
	for (int i = 0; i < n; ++i) {
		int u;
		cin >> u;
		cin >> node[u].k;
		for (int j = 0; j < node[u].k; ++j) {
			int v;
			cin >> v;
			node[u].v.push_back(v);
		}
		node[u].d = node[u].f = 0;
	}
	for (int i = 1; i <= n; ++i)
		dfs(i);
	for (int i = 1; i <= n; ++i)
		cout << i << " " << node[i].d << " " << node[i].f << endl;
	return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;
static const int WHITE = 0;
static const int GRAY  = 1;
static const int BLACK = 2;
static const int N     = 100;

int n, tt;
vector<vector<int>> M(N, vector<int>(N));
vector<int> color(N), d(N), f(N);

void dfs_visit(int u) {
  color[u] = GRAY;
  d[u]     = ++tt;
  for (int v = 0; v < n; v++) {
    if (M[u][v] == 0) continue;
    if (color[v] == WHITE) { dfs_visit(v); }
  }
  color[u] = BLACK;
  f[u]     = ++tt;
}

void dfs() {
  tt = 0;

  for (int u = 0; u < n; u++) {
    if (color[u] == WHITE) dfs_visit(u);
  }
  for (int u = 0; u < n; u++) {
    printf("%d %d %d\n", u + 1, d[u], f[u]);
  }
}

int main() {
  int u, v, k;
  cin >> n;
  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();
}

C++: #include<iostream>
#include<climits>
#include<vector>
#include<list>
#include<functional>
#include<algorithm>
#include<string>
#include<cmath>
#include<complex>
#include<set>
#include<map>
#include<stack>
#include<queue>
#include<deque>
#define FOR(i,a,b) for(int i=(a);i<(b);i++)
#define REP(i,n) for(int i=0;i<(n);i++)
#define INF (int)1e9
#define INFL (ll)1e11
using namespace std;
typedef long long ll;
typedef pair<int, int> P;

vector<int> d(100, 1), f(100);

int dfs(vector<vector<int>> a, int s) {
	int n = a.size();
	int res = 0;
	REP(j, n) {
		if (d[j] == 1 && a[s][j]) {
			if (res == 0) {
				d[j] = d[s] + 1;
			}
			else {
				d[j] = res;
			}
			res = dfs(a, j) + 1;
		}
	}
	if (res == 0) return f[s] = d[s] + 1;
	return f[s] = res;
}

int main() {
	cin.tie(0);
	ios::sync_with_stdio(false);

	int n;
	cin >> n;
	vector<vector<int>> a(n, vector<int>(n, 0));
	REP(i, n) {
		int u, k;
		cin >> u >> k;
		u--;
		REP(j, k) {
			int v;
			cin >> v;
			a[u][--v] = 1;
		}
	}
	dfs(a, 0);
	REP(i, n) {
		cout << i + 1 << " " << d[i] << " " << f[i] << "\n";
	}
	
	return 0;
}

C++: #include<iostream>
#include<vector>
using namespace std;
const int MAXN = 1000;
int n;
int d[MAXN];
int f[MAXN];
int t;
void solve(int current,vector<vector<int> > &g){
  if(d[current] > 0)return;
  t++;
  d[current] = t;
  for(int next:g[current]){
    solve(next,g);
  }
  t++;
  f[current] = t;
}

int main(){
  cin >> n;
  vector<vector<int> > g(n+1);
  for(int i = 1;i <= n;i++){
    int u,k;
    cin >> u >> k;
    for(int j = 0;j < k;j++){
      int v;
      cin >> v;
      g[i].push_back(v);
    }
  }
  solve(1,g);
  for(int i = 1;i <= n;i++){
    cout << i << ' ' << d[i] << ' ' << f[i] << endl;
  }
}

C++: /*16D8103008D 西村悠輝　nissy0507barista  alds11_B*/ 

#include<iostream>

#define MAX 110
using namespace std;

int n,v,k,u; ///超点数、頂点番号、出次数、隣接
int d[MAX], f[MAX];///タイムスタンプ
int a[MAX][MAX];
int cnt=0;
int flag[MAX]; ///通ったかどうか

void dfs(int x) {

	if (flag[x] == 1)return;
	cnt++;
	d[x] += cnt;
	flag[x] = 1;
	for (int i = 1; i <= n; i++) {
		if (a[x][i] == 1 && flag[i] == 0) dfs(i);
	}
	cnt++;
	f[x] += cnt;

}

int main(void)
{
	cin >> n;

	for (int i = 0; i < n; i++) {
		cin >> v >> k;
		for (int j = 0; j < k; j++) {
			cin >> u ;
			a[v][u]=1;
		}
	}
	
	for (int i = 1; i <= n; i++) dfs(i);

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

	return 0;
}