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)
	t := 1
	for i := 1; i <= n; i++ {
		t = dfs(&g, &d, &f, i, t)
	}

	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++: /*
 * ALDS1_11_B.cpp
 *
 *  Created on: May 5, 2018
 *      Author: 13743
 */

#include<iostream>
#include<vector>

using namespace std;

int d[101];
int f[101];
int nowTime;

void dfsRec(vector<int>* a, int n, int v) {
	if(d[v] > 0) return;
	nowTime++;
	d[v] = nowTime;
	for(int &x:a[v]) {
		dfsRec(a, n, x);
	}
	nowTime++;
	f[v] = nowTime;
}

int main() {
	int n;
	vector<int> adj[101];

	cin >> n;
	for(int i=0; i<n; i++) {
		int v;
		int k;
		cin >> v >> k;
		for(int j=0; j<k; j++) {
			int u;
			cin >> u;
			adj[v].push_back(u);
		}
	}

	for(int i=1; i<=n; i++) {
		if(d[i] ==0) dfsRec(adj, n, i);
	}

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

C++: /**
 * Depth first search.
 * start from node 1
 * 1) increment time 
 * 2) find non visited adjacent node
 * 3) if found move to that node.  d[v'] = time
 * 4) if not found. f[v] = time
 * 5) else end.
 * 5) go to 2.
 */

#include <iostream>
using namespace std;
const int N = 101;
int adj[N][N] = {0};
int d[N]={0};
int f[N]={0};
int t = 0;

void dfs(int n) {
	if (d[n]) return;
	d[n]=++t;
	int k = adj[n][0];
	for (int j=1;j<=k;j++) {
		dfs(adj[n][j]);
	}
	f[n]=++t;
}

int main()
{
	int n;
	cin >> n;
	for (int i=1;i<=n;i++){
		int j, k;
		cin >> j >> k;
		adj[j][0]=k;
		for (int m=1;m<=k;m++) {
			int a;
			cin >> a;
			adj[j][m]=a;
		}
	}

	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;
}

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

void Main()
{
  set<int> visited;
  stack<int> s;
  int n; cin >> n;
  vector<int> stt(n+1), end(n+1), K(n+1);
  vector<vector<int> > A(n+1, vector<int>(n+1));
  for(int i = 0; i < n; i++) {
    int u; cin >> u;
    cin >> K[u];
    for (int j = 0; j < K[u]; j++) cin >> A[u][j];
  }
  s.push(1);
  int time = 1;
  bool popped = false;
  while (true) {
    //if (!popped) time++;
    //popped = false;
    if (s.size() == 0) {
      for (int i = 1; i <= n; i++) {
        if (visited.find(i) == visited.end()) {
          s.push(i);
          break;
        }
      }
      if (s.size() == 0) break;
      else {time++; continue;}
    }
    int cur = s.top();
    //cout << time << ' ' <<  cur << endl;
    if (visited.find(cur) == visited.end()) {
      visited.insert(cur);
      stt[cur] = time;
    }
    bool done = true;
    for(int i = 0; i < K[cur]; i++) {
      int nxt = A[cur][i];
      if (visited.find(nxt) == visited.end()) {
      	s.push(nxt);
        time++;
        done = false;
        break;
      }
    }
    if (done) {
      time++;
      end[cur] = time;
      s.pop();
      popped = true;
    }
  }
  for(int i = 0; i < n+1; i++) {
    if (i==0) continue;
    cout << i << ' ' << 
      stt[i] << ' ' << end[i] << endl;
  }
}

int main()
{
  ios_base::sync_with_stdio(false);
  cout << fixed << setprecision(20);
  Main();
  return 0;
}

C++: #include<cstdio>
#include<cstdlib>
#include<cstring>
#include<vector>
using namespace std;
//http://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=ALDS1_11_B
//
#define N 105
vector<int> nebors[N];//start from 1
int start[N]; // start form 1
int end[N]; //end with 1

void dfs(int k,int d){
	start[k] = d;
	
	//check the adjencit list
	for(int i = 0; i<nebors[k].size(); i++){
		int temp = nebors[k].at(i);
		if(start[temp]==-1)
			dfs(temp,d+1);
	}
	end[k] = 9-d;
}

int main(){
	int n;
	scanf("%d",&n);
	memset(start,-1,sizeof(start));
	memset(end,-1,sizeof(end));
	for(int i = 1; i<=n; i++){
		int id,num;
		scanf("%d %d",&id, &num);
		for(int j = 0; j<num; j++){
			int temp;
			scanf("%d",&temp);
			nebors[id].push_back(temp);
			nebors[temp].push_back(id);
		}
	}
	dfs(1,1);
	
	for(int i = 1; i<=n; i++){
		printf("%d %d %d\n",i,start[i],end[i]);
	}
}

C++: #include <iostream>
#include <vector>

using namespace std;

int N,k[1000];
int v[1000][1000];
int found[1000] = {0},ended[1000] = {0};
int keep;
int checking=0;

void dfs(int cur);

int main() {
	cin >> N;
	for(int i=1;i<N+1;i++) {
		cin >> keep >> k[i];
		for(int j=1;j<k[i]+1;j++) {
			cin >> v[i][j];

		}
	}
	dfs(1);
	while(true) {
		//cout << "processing..." << endl;
		bool flag = false;
		int key = 1;
		for(int i=1;i<N+1;i++) {
			if(found[i] == 0) {
				flag = true;
				key = i;
				break;
			}
		}
		if(flag) {
			dfs(key);
		} else {
			break;
		}
	}
	
	
	for(int i=1;i<N+1;i++) {
		cout << i << " " << found[i] << " " << ended[i] << endl;
	}
	

}

void dfs(int cur) {
	//cout << "process ended" << endl;
	if(!found[cur]) {
		checking++;
		//cerr << "visiting: " << cur << " " << "time: " << checking << endl;
		found[cur] = checking;

	}
	for(int dst=1;dst<N+1;dst++) {
		bool flag = false;
		for(int i=1;i<k[cur]+1;i++) {
			if(v[cur][i] == dst) flag = true;
		}
		if((flag) && (dst != cur) && (!found[dst])) dfs(dst);
	}
	if(!ended[cur]) {
		checking++;
		//cerr << "ended: " << cur << " " << "time: " << checking << endl;
		ended[cur] = checking;
	}
}

C++: #include <iostream>
#include <stack>
using namespace std;
static const int N = 100;
static const int WHITE = 0;
static const int GRAY = 1;
static const int BLACK = 2;

int n, M[N][N];
int color[N], d[N], f[N], tt;
int nt[N];

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

void dfs_visit(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()
{
  for (int i = 0; i < n; i++)
  {
    color[i] = WHITE;
    nt[i] = 0;
  }
  tt = 0;

  for (int u = 0; u < n; u++)
  {
    if (color[u] == WHITE)
      dfs_visit(u);
  }

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

int main()
{
  int u, k, v;

  cin >> n;
  for (int i = 0; i < n; i++)
  {
    for (int j = 0; j < n; j++)
    {
      M[i][j] = 0;
    }
  }

  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();

  return 0;
}

C++: #include<iostream>
#include<cstring>
using namespace std;
#define MAX 100+5
int color[MAX],m[MAX][MAX],start[MAX],stop[MAX],a[MAX]; 
//color[i]中0--白色；1--灰色；2--黑色； 
int num;
int time1=0;
void dfs(int i){
	color[i]=1;start[i]=++time1;
	for(int j=1;j<=num;j++){
		if(m[i][j]==1&&color[j]==0){
			dfs(j);
		}
	}
	color[i]=2;stop[i]=++time1;
	return ;
}
int main(){
	memset(color,0,sizeof(color));
	memset(m,0,sizeof(m));
	cin>>num;
	for(int i=1;i<=num;i++){
		int cnt;
		cin>>a[i]>>cnt;
		for(int j=0;j<cnt;j++){
			int c;cin>>c;
			m[a[i]][c]=1;
		}
	}
	for(int i=1;i<=num;i++){
		if(color[i]==0)
		dfs(i);
	}
	for(int i=1;i<=num;i++){
		cout<<a[i]<<" "<<start[a[i]]<<" "<<stop[a[i]]<<endl;
	}
}