Go: package main

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

const MAX = 101

var f [MAX]int
var d [MAX]int
var list [][]int
var sc = bufio.NewScanner(os.Stdin)

func scanInt() int {
	num, _ := strconv.Atoi(scanString())
	return num
}

func scanString() string {
	sc.Scan()
	return sc.Text()
}

func init() {
	sc.Split(bufio.ScanWords)
}

func dfs(u, cnt int) int {
	if d[u] != 0 {
		return cnt
	}

	cnt++
	d[u] = cnt
	for _, next := range list[u] {
		cnt = dfs(next, cnt)
	}
	cnt++
	f[u] = cnt
	return cnt
}

func main() {
	n := scanInt()
	list = make([][]int, n+1)
	for i := 1; i <= n; i++ {
		u := scanInt()
		k := scanInt()
		for j := 0; j < k; j++ {
			n := scanInt()
			list[u] = append(list[u], n)
		}
	}

	cnt := 0
	for i := 1; i <= n; i++ {
		cnt = dfs(i, cnt)
	}

	w := bufio.NewWriter(os.Stdout)
	for i := 1; i <= n; i++ {
		fmt.Fprint(w, i)
		fmt.Fprint(w, " ")
		fmt.Fprint(w, d[i])
		fmt.Fprint(w, " ")
		fmt.Fprint(w, f[i])
		fmt.Fprintln(w)
	}
	w.Flush()
}

C++: // -*- mode:c++; coding:utf-8; c-basic-offset:2; -*-
// ALDS1_11_B: Depth First Search

#include <algorithm>
#include <cstdio>
#include <stack>
#include <utility>

using uint = unsigned int;

class Graph {
  const uint n_;
  uint* const g_;
  std::pair<uint, uint>* const visited_;
  
public:
  Graph(uint n) : n_(n),
                  g_(new uint[n_*n_]),
                  visited_(new std::pair<uint, uint>[n_])
  {
    init_graph();
  }

  ~Graph()
  {
    delete[] g_;
    delete[] visited_;
  }
  
  uint* operator [](uint i) const { return g_+(n_*i); }

  std::pair<uint, uint>* visited() const { return visited_; }

  void dfs()
  {
    std::stack<uint> s;
    auto time = 0u;
    init_visited();
    auto last_visited = 0u;
    s.push(0);
    visited_[0].first = time;
  outer_loop:
    while (!s.empty()) {
      auto i = s.top();
      for (auto j = last_visited+1; j < n_; ++j) {
        if ((*this)[i][j] && !visited_[j].first) {
          s.push(j);
          visited_[j].first = ++time;
          goto outer_loop;
        }
      }
      s.pop();
      visited_[i].second = ++time;
      last_visited = i;
    }
  }

private:
  void init_graph() { std::fill(g_, g_+(n_*n_), 0u); }

  void init_visited()
  {
    for (auto i = 0u; i < n_; ++i) {
      visited_[i].first = 0u;
    }
  }
};

int main()
{
  uint n;
  std::scanf("%u", &n);

  Graph g(n);

  uint u, k, v;
  for (auto i = 0u; i < n; ++i) {
    std::scanf("%u %u", &u, &k);
    for (auto j = 0u; j < k; ++j) {
      std::scanf("%u", &v);
      g[u-1][v-1] = 1;
    }
  }

  g.dfs();
  auto visited = g.visited();
  for (auto i = 0u; i < n; ++i) {
    std::printf("%u %u %u\n", i+1, visited[i].first+1, visited[i].second+1);
  }
}

// eof

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

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

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

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;
}

C++: //
// Created by tattsun on 2017/02/13.
//

#include <iostream>
#include <vector>

using namespace std;

#define VERTEX_MAX_NUM 101
#define NIL -1

int now = 0;
int n;
int start[VERTEX_MAX_NUM];
int finish[VERTEX_MAX_NUM];
bool visited[VERTEX_MAX_NUM];
vector<int> vertexes[VERTEX_MAX_NUM];

void _dfs(int node) {
    start[node] = ++now;
    visited[node] = true;

    auto& v = vertexes[node];
    for(auto it = v.begin(); it != v.end(); it++) {
        if(visited[*it])
            continue;
        _dfs(*it);
    }

    finish[node] = ++now;
}

void dfs() {
    _dfs(1);
}

int main() {
    for(int i=0; i<VERTEX_MAX_NUM; i++) {
        start[i] = NIL;
        finish[i] = NIL;
        visited[i] = false;
    }

    cin >> n;

    int u, k, p;
    for(int i=1; i<=n; i++) {
        cin >> u >> k;
        for(int j=0; j<k; j++) {
            cin >> p;
            vertexes[i].push_back(p);
        }
    }

    dfs();

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

C++: #include<iostream>
#include<vector>
#define SIZE 1000000
using namespace std;

struct Stack{
  int line[SIZE];
  int top;
  void init(){
    top = 0;
  }
  bool empty(){
    return top==0;
  }
  void push(int x){
    line[top]=x;
    top ++;
  }
  int pop(){
    if(empty()) return -1;
    top--;
    return line[top];
  }
};
struct Node
{
  vector<int> toList;
  int dt;
  int ft;
};

Stack stack; 
int t; //time

void init(vector<Node>& nodes)
{
  t=0;
  stack.init();
  stack.push(0);
  for(int i=0;i<nodes.size();i++){
    nodes[i].ft=-1;
    nodes[i].dt=-1;
  }
}
void print(vector<Node> nodes)
{
  int n=nodes.size();
  for(int i=0;i<n;i++){
    cout<<i+1<<" "<<nodes[i].ft<<" "<<nodes[i].dt<<endl;
  }
}
void dfs(vector<Node>& nodes)
{ 
  int idx=stack.pop();
  if(idx<0){
    for(int i=0;i<nodes.size();i++){
      if(nodes[i].ft<0){
	idx=i;
	break;
      }
    }
  }
  //cout<<idx+1<<":";
  if(idx>=0){
    if(nodes[idx].ft<0){
      //cout<<" find";
      t++;
      nodes[idx].ft=t;
    }
    if(nodes[idx].toList.size()<=0){
      //cout<<" toList.size==0"<<endl;
      t++;
      nodes[idx].dt=t;
      dfs(nodes);
    }
    int count=0;
    for(int i=0;i<nodes[idx].toList.size();i++){
      if(nodes[nodes[idx].toList[i]].ft<0){
	//cout<<" jumpto "<<i+1<<endl;
	count++;
	stack.push(idx);
	stack.push(nodes[idx].toList[i]);
	dfs(nodes);
      }
    }
    if(count==0 && nodes[idx].dt<0){
      //cout<<" finish"<<endl;
      t++;
      nodes[idx].dt=t;
      dfs(nodes);
    }
  }else{
    //cout<<"finish dfs"<<endl;
  }
}

int main()
{
  int n,u,k;
  cin>>n;
  vector<Node> nodes(n);
  for(int i=0;i<n;i++){
    cin>>u>>k;
    nodes[i].toList.resize(0);
    for(int j=0;j<k;j++){
      int tmp;
      cin>>tmp;
      nodes[i].toList.push_back(tmp-1);
    }
  }
  init(nodes);
  //print(nodes);

  dfs(nodes);
  print(nodes);
  return 0;
}

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

#define rep(i,n) for(int i=0;i<(int)(n);i++)
#define FOR(i,n,m) for(int i=(int)(n); i<=(int)(m); i++)
#define RFOR(i,n,m) for(int i=(int)(n); i>=(int)(m); i--)
#define ITR(x,c) for(__typeof(c.begin()) x=c.begin();x!=c.end();x++)
#define RITR(x,c) for(__typeof(c.rbegin()) x=c.rbegin();x!=c.rend();x++)
#define setp(n) fixed << setprecision(n)

template<class T> bool chmax(T &a, const T &b) { if (a<b) { a=b; return 1; } return 0; }
template<class T> bool chmin(T &a, const T &b) { if (a>b) { a=b; return 1; } return 0; }

#define ll long long
#define vll vector<ll>
#define vi vector<int>
#define pll pair<ll,ll>
#define pi pair<int,int>

#define all(a) (a.begin()),(a.end())
#define rall(a) (a.rbegin()),(a.rend())
#define fi first
#define se second
#define pb push_back
#define mp make_pair
#define ins insert

using namespace std;

const int MAX_N = 100;

int N;
vi G[MAX_N];
int d[MAX_N];
int f[MAX_N];

void dfs(int v=0)
{
    static int t=1;
    d[v] = t++;
    for(auto u:G[v]){
        if (d[u]>0) continue;
        dfs(u);
    }
    f[v] = t++;
}

//-------------------------------------------------

int main(void)
{
    cin.tie(0);
    ios::sync_with_stdio(false);
    cin>>N;
    rep(i,N){
        int u,k; cin>>u>>k; u--;
        rep(i,k){
            int v; cin>>v; v--;
            G[u].pb(v);
        }
    }
    rep(i,N)if(d[i]==0){
        dfs(i);
    }
    rep(i,N){
        cout<<i+1<<" "<<d[i]<<" "<<f[i]<<"\n";
    }
    return 0;
}