Go: package main

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

var N int
var A [][]int
var t int
var color, d, f []int

const (
	WHITE = iota
	GRAY
	BLACK
)

func dfsVisit(u int) {
	color[u] = GRAY
	t ++
	d[u] = t
	for v:=0; v<N; v++ {
		if A[u][v] == 0 {
			continue
		}
		if color[v] == WHITE {
			dfsVisit(v)
		}
	}
	color[u] = BLACK
	t++
	f[u] = t
}

func dfs() {
	for u:=0; u<N; u++ {
		if color[u] == WHITE {
			dfsVisit(u)
		}
	}
	for u:=0; u<N; u++{
		fmt.Printf("%d %d %d\n", u+1, d[u], f[u])
	}
}


func nextInt(scanner *bufio.Scanner) int {
	scanner.Scan()
	num, _ := strconv.Atoi(scanner.Text())
	return num
}

func main() {
	scanner := bufio.NewScanner(os.Stdin)
	scanner.Split(bufio.ScanWords)
	N = nextInt(scanner)
	color = make([]int, N)
	d = make([]int, N)
	f = make([]int, N)
	A = make([][]int, N)
	for i:=0; i<N; i++{
		A[i] = make([]int, N)
	}
	for i:=0; i<N; i++{
		index := nextInt(scanner) - 1
		cnt := nextInt(scanner)
		for j:=0; j<cnt; j++ {
			v := nextInt(scanner) - 1
			A[index][v] = 1
		}
	}
	dfs()
}

C++: #include<stdio.h>
#define MAX 102
#define WHITE 0
#define BLACK 1
#define GRAY 2


void init();
void visit(int);

int col[MAX];
int n, t = 0;
int d[MAX],f[MAX],edge[MAX],num[MAX][MAX],G[MAX][MAX];

void init(){

  int i,j;

  for(i = 0; i <= n; i++){
      col[i] = WHITE;
    }

}

void dFSearch(){
  int i;
  for(i = 1; i <= n; i++){
    if(col[i] == WHITE) visit(i);
  }
}

void visit(int u){
  int i,j;

  col[u] = GRAY;
  t += 1;
  d[u] = t;

  for(j = 0; j < n; j++){
    if(G[u][j] == 10) {
      if(col[j+1] == WHITE ){
    visit(j+1);
      }
    }
  }

  col[u] = BLACK;
  t = t + 1;
  f[u] = t;

}


int main(){

  int i,j,k = 0,vertex,number;

  scanf("%d\n",&n);
  init();

  for(i = 1; i <= n; i++){
    scanf("%d %d",&vertex,&edge[i]);
    for(j = 1; j <= edge[i]; j++){
      scanf("%d",&number);
      G[vertex][number-1] = 10;
    }
    scanf("\n");
  }

 dFSearch();

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

  return 0;


}

C++: #include <iostream>

using namespace std;

const int N = 100;
int A[N][N] = {{0}};
int n;
int t = 0;
int d[N] = {0};
int f[N] = {0};

void dfs(int id) {
    ++t;
    // cerr << "begin: " <<  id << " " << t << endl;
    if (d[id] == 0)
        d[id] = t;

    for (int i = 0; i < n; ++i) {
        if (A[id][i] != 0) {
            dfs(i);
        }
    }

    // cerr << "end: " <<  id << " " << t << endl;
    ++t;
    f[id] = t;
}

int main() {
    cin >> n;
    for (int i = 0; i < n; ++i) {
        int u;
        cin >> u;

        int k;
        cin >> k;
        for (int j = 0; j < k; ++j) {
            int x;
            cin >> x;
            A[u-1][x-1] = 1;
        }
    }

    dfs(0);

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

    return 0;
}

C++: #include <iostream>
using namespace std;
int cnt = 1;
void DepthFirstSearch(int now,int n,int a[][],int b[],int c[],int d[]){
  b[now]=1;
  c[now]=cnt;
  cnt++;
    for(int i=0;i<n;i++){
        if(a[now][i] && b[i]!=1){
            DepthFirstSearch(i,n,a,b,c,d);
            cnt++;
        }
    }
  d[now]=cnt;
}
int main(){
  int a[100][100],b[100],c[100],d[100]
  int n,u,m,num;
  cin>>n;
  for(int i = 0;i < n;i++){
    cin>>u>>m;
    for(int j = 0;j < m;j++){
      cin >> num;
      a[u-1][num-1]=1;
    }
  }
    for(int i=0;i<n;i++){
       if(b[i]!=1){
         DepthFirstSearch(i,n,a,b,c,d);
         cnt++;
       }
    }
  
    for(int i=0;i<n;i++){
        cout<< i+1 << " " << c[i] << " " << d[i]<<endl;
    }
  return 0;
  
}

C++: // http://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=ALDS1_11_C
// stackのパターン
// 実習資料では「srcの訪問時刻は0」となっているが、題意は1である。

#include <iostream>
#include <cstdio>
#include <stack> // 入れたものから出していく引っ越しトラック型の構造。
using namespace std;

int G[110][110];
int n;
int u, k, v;

void make_matrix() {
  fill(&G[0][0], &G[0][0]+110*110, 0);
  scanf("%d", &n);
  for (int i=0; i<n; i++) {
    scanf("%d%d", &u, &k);
    u--;
    for (int j=0; j<k; j++) {
      scanf("%d", &v);
      v--;
      G[u][v] = 1;
    }
  }
}

int timer; // timeだとエラーが出たので。
int d[110]; // 訪問時刻。ナマの数字を入れる(indexを-1処理しない)。
int f[110]; // 終了時刻。ナマの数字を入れる。
int parent[110]; // 訪問する原因となった数字を入れる。ナマの数字を入れる。
int children[110]; // Stackに追加した頂点の数。

void init() {
  timer = 1;
  fill(d, d+110, -1);
  fill(f, f+110, -1);
  fill(parent, parent+110, -1);
  fill(children, children+110, 0);
}

void dfs(int src) {
  // cerr << "dfs root is " << src << endl;
  stack<int> S; // todo訪問先
  S.push(src);
  while (! S.empty()) {
    int cur = S.top(); // 一番最近入れた数字を訪問。
    d[cur] = timer;
    timer++;
    S.pop();
    // cerr << "visiting " << cur << " at the time " << d[cur] << endl;
    for (int i=n; i>=1; i--) { // 節点i。逆順に入れていくことに注意！
      if (G[cur-1][i-1] == 1 && d[i] == -1) {
	S.push(i);
	parent[i] = cur;
	children[cur]++;
      }
    }
    int hantei = cur;
    while (hantei != -1 && children[hantei] == 0) {
      f[hantei] = timer;
      timer++;
      hantei = parent[hantei];
      children[hantei]--;
    }
  }
}

int main() {
  make_matrix();
  init();
  for (int i=1; i<=n; i++) { // 1から連結していない連結成分にも番号をふる。
    if (d[i] == -1) {
      dfs(i);
    }
  }
  for (int i=1; i<=n; i++) {
    printf("%d %d %d\n", i, d[i], f[i]);
  }
}

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