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 <cstdio>

typedef struct Node {
    int id;
    int d;
    int f;
    int count;
} Node;


int count(int id, int now, Node *node, int a[101][100]){
    if(node[id].d == 0) node[id].d = now;
    if(node[id].f != 0) return now - 1;
    if(node[id].count == 0){
        node[id].f = now + 1;
        return node[id].f;
    }
    for(int i = 0; i < node[id].count; ++i){
        int nextId = a[id][i];
        now = count(nextId, now + 1, node, a);
    }
    node[id].f = now + 1;
    return node[id].f;
}

int main(){
    int n;
    std::scanf("%d", &n);
    Node node[101];
    int a[101][100];
    for(int i = 1; i <= n; ++i){
        int id;
        std::scanf("%d", &id);
        node[id].id = id;
        std::scanf("%d", &node[id].count);
        for(int j = 0; j < node[id].count; ++j){
            std::scanf("%d", &a[i][j]);
        }
    }
    count(1, 1, node, a);
    for(int i = 1; i <= n; ++i){
        std::printf("%d %d %d\n", node[i].id, node[i].d, node[i].f);
    }

    return 0;
}

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

int time1 = 0;
int a[110][110] = {};
int d[110] = {};
int f[110] = {};
int n;
int p;

void dfs(int cur){
  if(d[cur]==0){
    d[cur] = time1;
  }
  time1 += 1;
  f[cur] = time1;

  for(int dst=1;dst<=n;dst++){
    if(a[cur][dst]==1&&d[dst]==0){
      a[cur][dst]=2;
      dfs(dst);
    }
  }
  for(int k=1;k<=n;k++){
    if(a[k][cur]==2){
      a[k][cur]=1;
      p+=1;
      dfs(k);
    }else{
      p=0;
    }
  }
  if(p==0){
    for(int k=1;k<=n;k++){
      if(d[k]==0){
	time1+=1;
	dfs(k);
      }
    }
  }
}

int main(){
  cin>>n;
  for(int i=1;i<=n;i++){
    int u,k;
    cin>>u>>k;
    for(int j=0;j<k;j++){
      int v;
      cin>>v;
      a[i][v]=1;
    }
  }
  time1 += 1;
  dfs(1);
  for(int k=1;k<=n;k++){
    cout<<k<<" "<<d[k]<<" "<<f[k]<<endl;
  }
}

C++: #include<cstdio>
#include<functional>
#include<algorithm>
using namespace std;
void func(int);
int n,k[101],v[101][100],d[101],f[101],cnt;
int flg[101];
int main(void)
{
	int i,u,j;
	scanf("%d",&n);
	for(i=1;i<=n;i++)	{
		scanf("%d %d",&u,&k[i]);
		for(j=0;j<k[i];j++)	scanf("%d",&v[i][j]);
	}
	for(i=1;i<=n;i++)	flg[i]=0;
	cnt=0;
	for(i=1;i<=n;i++)	{
		if(flg[i]==0)		func(i);
	}
	for(i=1;i<=n;i++)	printf("%d %d %d\n",i,d[i],f[i]);
	return 0;
}
void func(int nn)
{
	int i;
	cnt++;	
	d[nn]=cnt;
	flg[nn]=1;
	for(i=0;i<k[nn];i++)	{
		if(flg[v[nn][i]]==0)	{
			func(v[nn][i]);
		}
	}
	cnt++;
	f[nn]=cnt;
}

C++: #include <bits/stdc++.h>
 
using namespace std;

vector<vector<int>> g;
vector<int> s, e;

void dfs(int v, int& t) {
    if (s[v]) return;
    s[v] = t++;
    for (auto& x : g[v]) {
        dfs(x, t);
    }
    e[v] = t++;
}

int main() {
    int n; cin >> n;
    g.resize(n); s.resize(n); e.resize(n);
    for (int i = 0; i < n; i++) {
        int u, k; cin >> u >> k; u--;
        while (k--) {
            int v; cin >> v; v--;
            g[u].push_back(v);
        }
        sort(g[u].begin(), g[u].end());
    }
    int t = 1;
	for (int i = 0; i < n; i++) dfs(i, t);
    for (int i = 0; i < n; i++) {
        cout << i + 1 << " " << s[i] << " " << e[i] << endl;
    }
}

C++: #include <bits/stdc++.h>

using namespace std;

typedef long long int ll;
typedef pair<ll, ll> pll;

#define FOR(i, n, m) for(ll (i)=(m);(i)<(n);++(i))
#define REP(i, n) FOR(i,n,0)
#define OF64 std::setprecision(10)

const ll MOD = 1000000007;
const ll INF = (ll) 1e15;

struct Vertex {
    vector<ll> node;
};

ll N;
Vertex V[105];
pll ans[105];

void dfs(ll idx, ll &time) {
    ans[idx].first = time++;
    for (auto &nxt:V[idx].node) {
        if (ans[nxt].first > 0)
            continue;
        dfs(nxt, time);
    }
    ans[idx].second = time++;
}

int main() {
    cin.tie(0);
    ios::sync_with_stdio(false);
    cin >> N;
    REP(i, N) {
        ll n, k;
        cin >> n >> k;
        n--;
        REP(j, k) {
            ll v;
            cin >> v;
            v--;
            V[n].node.push_back(v);
        }
    }
    REP(i, N) {
        ans[i] = pll(0, 0);
    }
    ll time = 1;
    REP(i, N) {
        if (ans[i].first > 0)
            continue;
        dfs(i, time);
    }
    REP(i, N) {
        cout << i + 1 << " " << ans[i].first << " " << ans[i].second << endl;
    }
    return 0;
}