Go: package main

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

var sc = bufio.NewScanner(os.Stdin)
var depth [101]int
var finish [101]int
var d [101]int
var n, time int

func nextInt() int {
	sc.Scan()
	i, _ := strconv.Atoi(sc.Text())
	return i
}
func visit(graph [][]int, u int) {
	depth[u] = 1
	time++
	d[u] = time
	for i := 0; i < n; i++ {
		if graph[u][i] == 1 {
			if depth[i] == 0 {
				visit(graph, i)
			}
		}
	}
	depth[u] = 2
	time++
	finish[u] = time
}
func main() {
	sc.Split(bufio.ScanWords)

	n = nextInt()
	graph := make([][]int, n)
	for i := 0; i < n; i++ {
		graph[i] = make([]int, n)
	}
	for i := 0; i < n; i++ {
		s := nextInt()
		t := nextInt()
		if t == 0 {
			continue
		}
		for i := 0; i < t; i++ {
			u := nextInt()
			graph[s-1][u-1] = 1
		}
	}
	for i := 0; i < n; i++ {
		if depth[i] == 0 {
			visit(graph, i)
		}
	}
	for i := 0; i < n; i++ {
		fmt.Printf("%d %d %d\n", i+1, d[i], finish[i])
	}
}

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

int a[101][101];
int n = 0;
int found[101];
int ended[101];
int aaa(int i, int time);

int main() {
  for (int i = 0; i < 101; i++)
    for (int j = 0; j < 101; j++)
	  a[i][j] = 0;
  int u, k, v;
  cin >> n;
  for (int i = 0; i < n; i++) {
    cin >> u >> k;
	for (int j = 0; j < k; j++) {
	  cin >> v;
	  a[u][v] = 1;
	  }
	 }
int time = 0;
for (int i = 0; i < 101; i++){
  found[i] = 0;
  ended[i] = 0;
  }
for (int i = 0; i < n+1; i++) {
  if(found[i] > 0)
    continue;
  time++;
  found[i]=time;
  time=aaa(i,time);
  ended[i]=time;
  }
  
for (int i = 1; i < n+1; i++) {
 cout << i << ' ' << found[i] << ' ' << ended[i] << endl;
 }
 
}
 
int aaa(int i, int time) {
  for (int k = 1; k < n+1; k++) {
    if (a[i][k] == 1 && found[k] == 0) {
	  time++;
	  found[k] = time;
	  time = aaa(k,time);
	  ended[k] = time;
	  }
	 }
	time++;
	return time;
	}

C++: #include <iostream>

using namespace std;

int adja[101][101];
int d[101], f[101], cnt;

void dfs(int u) {
    d[u] = ++cnt;
    for (int i = 0, v; (v = adja[u][i]) > 0; ++i) {
        if (d[v] > 0)
            continue;
        dfs(v);
    }
    f[u] = ++cnt;
}

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

    return 0;
}