Go: package main

import (
	"fmt"
)

func main() {
	var n int
	fmt.Scan(&n)
	g := make([][]int, n+1)
	for i := 0; i < n; i++ {
		var u,k int
		fmt.Scan(&u)
		fmt.Scan(&k)
		g[u] = make([]int, k)
		for j := 0; j < k; j++ {
			fmt.Scan(&g[u][j])
		}
	}

	d := make([]int, n+1)
	f := make([]int, n+1)
	dfs(&g, &d, &f, 1, 1)

	for i := 1; i <= n; i++ {
		fmt.Printf("%d %d %d\n", i, d[i], f[i])
	}
}

func dfs(g *[][]int, d *[]int, f *[]int, id int, t int) int {
	if (*d)[id] > 0 {
		return t
	}
	(*d)[id] = t
	t += 1
	for i := 0; i < len((*g)[id]); i++ {
		t = dfs(g, d, f, (*g)[id][i], t)
	}
	(*f)[id] = t
	return t+1
}

C++: #include <iostream>
#include <vector>
using namespace std;
typedef vector <int> vi;
typedef vector <vi> vvi;
int counter=0;

int addedge(vvi &graph, int y, int x, int val=1){
	graph[y][x] = val;
	return val;
}

int make_graph(vvi &graph, vvi &stamp){
	int n1=graph.size(), n2, row, col;

	for (int j=0; j<n1; j++){
		cin>>row;
		cin>>n2;
		for (int i=0; i<n2; i++){
			cin>>col;
			addedge(graph, row-1, col-1);
		}
		stamp[j][0] = -1;
	}
	return 0;
}

int Depth_First_Search(vvi &graph, vvi &stamp, int key=0){
	if (stamp[key][0] != -1) return 0;
	stamp[key][0] = ++counter;
	for (int i=0; i<int(graph[0].size()); i++){
		if (graph[key][i]==1 && stamp[i][0]==-1){
			Depth_First_Search(graph, stamp, i);
		}
	}
	stamp[key][1] = ++counter;
	return 0;
}

int resultout(vvi &stamp){
	for (int i=0; i<int(stamp.size()); i++){
		cout<<i+1<<" "<<stamp[i][0]<<" "<<stamp[i][1]<<endl;
	}
	return 0;
}

int main(void){

	int n, row;
	cin>>n;
	vvi G(n, vi(n)), stamp(n, vi(2));

	make_graph(G, stamp);

	for (int i=0; i<n; i++){
		Depth_First_Search(G, stamp, i);
	}
	resultout(stamp);

	return 0;
}

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

int n;
int M[100][100];
int color[100], d[100], f[100];
int time = 1;

void Dfs(int u) {
  color[u] = 1;
  d[u] = time;
  time++;
  for (int v = 0; v < n; v++) if (M[u][v] && color[v] == 0) Dfs(v);
  color[u] = 2;
  f[u] = time;
  time++;
}

int main() {
  cin >> n;

  for (int i = 0; i < n; i++) {
    int u, k;
    cin >> u >> k;
    u--;
    for (int j = 0; j < k; j++) {
      int v;
      cin >> v;
      v--;
      M[u][v]++;
    }
  }

  Dfs(0);

  for (int i = 0; i < n; i++) cout << i + 1 << " " << d[i] << " " << f[i] << endl;

  return 0;
}

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

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

  int V[100][100]; //隣接リスト
  int cnt[100]; //各点においてどこまでみたかの把握
  int d[100];
  int f[100];
  int time=1;
  int l=0;
  int come[100]; //その点はどこからきたかの把握

  //初期化
  for(int i=0;i<100;i++){
    for(int j=0;j<100;j++){
      V[i][j]=0;
      cnt[j]=0;
      d[j]=0;
      f[j]=0;
      come[j]=0;
    }
  }
  //グラフ情報の読み込み
 int  m=0;
  for(int i=0;i<n;i++){
    cin>>u;
    cin>>k;
    for(int j=0;j<k;j++){
      cin>>v;
      V[u-1][m]=v;
      m++;
    }
    m=0;
  }


  //スタートは0
 d[0]=1;
 time++;
  while(1){

    if(time==2*n+1) break;
    //先がありかつそこは探索終了していない
    if(V[l][cnt[l]]!=0 && f[V[l][cnt[l]]-1]==0){ 
     
      if(d[V[l][cnt[l]]-1]==0) d[V[l][cnt[l]]-1]=time;

   come[V[l][cnt[l]]-1]=l;
      cnt[l]++;
      l=V[l][cnt[l]-1]-1; 

      time++;
      //先がないまたはさきが探索終了している
    }else{

      if(d[l]==0) d[l]=time;
       f[l]=time;
      l=come[l];
      time++;

    }

  }
  /*
  for(int i=0;i<n;i++){
    for(int j=0;j<n;j++){
    cout<<V[i][j]<<" ";
    if(j==n-1) cout<<endl;
  }
  }
  */
  //出力
  for(int i=0;i<n;i++){

    cout<<i+1<<" "<<d[i]<<" "<<f[i]<<endl;
    }


  return 0;
}

C++: //#include <bits/stdc++.h>
#include<iostream>
#include<stack>
#define MAX 100
#define BLACK 2
#define WHITE 0
#define GRAY 1
using namespace std;

void dfsInit();
void dfs(int);
int next(int);

int n,A[MAX][MAX];
int color[MAX],d[MAX],f[MAX],nt[MAX];
int time1;
int main(){
  int i,j,u,v,k;
  cin >> n;
  for(i = 0; i < n; i++){
    for(j = 0; j< n; j++){
      A[i][j] = 0;
    }
  }
  for(i = 0; i < n; i++){
    cin >> u;
    cin >> k;
    u = u-1;
    for(j = 0; j < n; j++){
      cin >> v;
      v = v-1;
      A[u][v] = 1;
    }
  }
  dfsInit();
  return 0;
}

void dfsInit(){
  for(int i = 0; i < n; i++){
    color[i] = WHITE;
    nt[i] = 0;
  }
  time1 = 0;
  for(int u = 0; u < n; u++){
    if(color[u] == WHITE){
      dfs(u);
    }
  }
  for(int i = 0; i < n; i++){
    //printf("%d %d %d\n",i+1,d[i],f[i]);
    cout << i+1 << " " << d[i] << " " << f[i] << endl;
  }
}

int next(int u){
  int v;
  for(v = nt[u]; v < n; v++){
    nt[u] = v+1;
    if(0 < A[u][v]){
      return v;
    }
  }
  return -1;
}
void dfs(int u){
  for(int i = 0; i < n; i++){
    nt[i] = 0;
  }
  stack<int> S;
  S.push(u);
  color[u] = GRAY;
  d[u] = ++time1;
  while(!S.empty()){
    int r = S.top();
    int v = next(u);
    if(v != -1){
      if(color[v] == WHITE){
        color[v] = GRAY;
        d[v] = ++time1;
        S.push(v);
      }
    }
    else{
      S.top();
      color[r] = BLACK;
      f[r] = ++time1;
    }
  }
}

C++: #include <map>
#include <set>
#include <list>
#include <cmath>
#include <deque>
#include <queue>
#include <stack>
#include <cstdio>
#include <string>
#include <vector>
#include <complex>
#include <cstdlib>
#include <cstring>
#include <numeric>
#include <utility>
#include <iostream>
#include <algorithm>
#include <functional>
#include <unordered_map>
#include <unordered_set>

using namespace std;

#define ll long long
#define ull unsigned long long
#define INF (1 << 30)
#define LLINF (1LL << 62)
#define MOD7 1000000007
#define MOD9 1000000009
#define eps 1e-9
#define P pair<int, int>
#define pii pair<int, int>
#define pll pair<ll, ll>
#define pul pair<ull, ull>
#define all(a) (a).begin(), (a).end()
#define FOR(i,a,b) for (int i=(a);i<(b);++i)
#define RFOR(i,a,b) for (int i=(b)-1;i>=(a);--i)
#define REP(i,n) for (int i=0;i<(n);++i)
#define RREP(i,n) for (int i=(n)-1;i>=0;--i)

void YES() { cout << "YES\n"; }
void NO() { cout << "NO\n"; }
void Yes() { cout << "Yes\n"; }
void No() { cout << "No\n"; }
void yes() { cout << "yes" << endl; }
void no() { cout << "no" << endl; }

template<class T>
class DirectedGraph {
public:
	class Edge {
	public:
		int to;
		T cost;

		Edge(int t, T c) : to(t), cost(c) {}
	};

	vector<vector<Edge>> G;
	vector<int> visit;
	vector<pii> stamp{ 0 };
	int V;

	DirectedGraph(int n = 0) {
		resize(n);
	}

	void resize(int n) {
		V = n;
		G.resize(n);
		visit.resize(n);
		stamp.resize(n);
	}

	void addEdge(int from, int to, T cost = 0) {
		int v = max(from, to);
		if (v >= V)
			resize(v + 1);
		G[from].push_back(Edge(to, cost));
	}

	int t = 1;
	void dfs(int s) {
		if (stamp[s].first == 0)
			stamp[s].first = t++;
		else
			return;

		for (int i = 0; i < G[s].size(); ++i) {
			dfs(G[s][i].to);
		}
		stamp[s].second = t++;
	}

	int bfs() {

	}
};

int main() {
	DirectedGraph<int> g;
	int n, id, k, to;
	cin >> n;
	for (int i = 0; i < n; ++i) {
		cin >> id >> k;
		while (k--) {
			cin >> to;
			g.addEdge(id, to);
		}
	}

	for (int i = 1; i <= n; ++i) {
		g.dfs(i);
	}
	for (int i = 1; i <= n; ++i) {
		cout << i << " " << g.stamp[i].first << " " << g.stamp[i].second << endl;
	}

	return 0;
}