Go: package main

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

func getScanner(fp *os.File) *bufio.Scanner {
	scanner := bufio.NewScanner(fp)
	scanner.Split(bufio.ScanWords)
	scanner.Buffer(make([]byte, 1000005), 1000005)
	return scanner
}

func getNextString(scanner *bufio.Scanner) string {
	scanner.Scan()
	return scanner.Text()
}

func getNextInt(scanner *bufio.Scanner) int {
	i, _ := strconv.Atoi(getNextString(scanner))
	return i
}

func getNextInt64(scanner *bufio.Scanner) int64 {
	i, _ := strconv.ParseInt(getNextString(scanner), 10, 64)
	return i
}

func getNextUint64(scanner *bufio.Scanner) uint64 {
	i, _ := strconv.ParseUint(getNextString(scanner), 10, 64)
	return i
}

func getNextFloat64(scanner *bufio.Scanner) float64 {
	i, _ := strconv.ParseFloat(getNextString(scanner), 64)
	return i
}

func main() {
	fp := os.Stdin
	wfp := os.Stdout
	cnt := 0

	if os.Getenv("MASPY") == "ますピ" {
		fp, _ = os.Open(os.Getenv("BEET_THE_HARMONY_OF_PERFECT"))
		cnt = 1
	}
	if os.Getenv("MASPYPY") == "ますピッピ" {
		wfp, _ = os.Create(os.Getenv("NGTKANA_IS_GENIUS10"))
	}

	scanner := getScanner(fp)
	writer := bufio.NewWriter(wfp)
	solve(scanner, writer)
	for i := 0; i < cnt; i++ {
		fmt.Fprintln(writer, "-----------------------------------")
		solve(scanner, writer)
	}
	writer.Flush()
}

func solve(scanner *bufio.Scanner, writer *bufio.Writer) {
	n := getNextInt(scanner)
	g := graph{}
	g.ee = make([]Edges, n)
	g.visited = make([]bool, n)
	g.found = make([]int, n)
	g.leave = make([]int, n)
	for i := 0; i < n; i++ {
		u := getNextInt(scanner) - 1
		k := getNextInt(scanner)
		for j := 0; j < k; j++ {
			v := getNextInt(scanner) - 1
			g.ee[u] = append(g.ee[u], Edge{
				to: v,
				id: u,
			})
		}
	}
	for i := 0; i < n; i++ {
		sort.Sort(g.ee[i])
	}
	for i := 0; i < n; i++ {
		if g.visited[i] {
			continue
		}
		g.dfs(i)
	}

	for i := 0; i < n; i++ {
		fmt.Fprintln(writer, fmt.Sprintf("%d %d %d", i+1, g.found[i], g.leave[i]))
	}
}

// Edge ...
type Edge struct {
	to, id int
}

type Edges []Edge

func (a Edges) Len() int           { return len(a) }
func (a Edges) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }
func (a Edges) Less(i, j int) bool { return a[i].id < a[j].id }

type graph struct {
	ee           []Edges
	t            int
	n            int
	visited      []bool
	found, leave []int
}

func (g *graph) dfs(i int) {
	g.visited[i] = true
	g.t++
	g.found[i] = g.t
	for _, e := range g.ee[i] {
		if g.visited[e.to] {
			continue
		}
		g.dfs(e.to)
	}
	g.t++
	g.leave[i] = g.t
}

C++: #include <iostream>
#include <stack>
using namespace std;
static const int MAX = 100;
static const int NIL = -1;
static const int WHITE = 0;
static const int GRAY = 1;
static const int BLACK = 2;
int M[MAX][MAX], n, tt = 0;
int d[MAX], f[MAX], color[MAX];
stack<int> S;

int next(int v)
{
    for (int i = 0; i != n; ++i)
    {
        if (M[v][i] != 0)
        {
            if (color[i] == WHITE)
            {
                return i;
            }
        }
    }
    return NIL;
}

void dfs(int u)
{
    int v;
    S.push(u);
    color[u] = GRAY;
    d[u] = ++tt;
    while (S.size())
    {
        u = S.top();
        v = next(u);
        if (v != NIL)
        {
            S.push(v);
            color[v] = GRAY;
            d[v] = ++tt;
        }
        else
        {
            S.pop();
            color[u] = BLACK;
            f[u] = ++tt;
        }     
    }
}

int main()
{
    int id, m, v;
    cin >> n;
    for (int i = 0; i != MAX; ++i)
    {
        d[i] = 0;
        f[i] = 0;
        color[i] = WHITE;
        for (int j = 0; j != MAX; ++j)
        {
            M[i][j] = 0;
        }
    }
    for (int i = 0; i != n; ++i)
    {
        cin >> id >> m;
        for (int j = 0; j != m; ++j)
        {
            cin >> v;
            M[id-1][v-1] = 1;
        }
    }
    for (int i = 0; i != n; ++i)
    {
        if (color[i] == WHITE) dfs(i);
    }

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

C++: #include <iostream>
#include <vector>
using namespace std;
vector<vector<int> > v(101);
int dp[101][2] = { 0 };
int n, t = 0;

void dfs(int a) {
	if (dp[a][0] == 0) { t++; dp[a][0] = t; }
	else { return; }
	for (int i = 0;i < v[a].size();i++) {
		if (dp[v[a][i]][0] == 0) {
			dfs(v[a][i]);
		}
	}
	if (dp[a][1] == 0) { t++; dp[a][1] = t; }
}

int main() {
	cin >> n;
	for (int i = 0; i < n;i++) {
		int u,k; cin >> u >> k;
		for (int j = 0; j < k;j++) {
			int x; cin >> x;
			v[u].push_back(x);
		}
	}
	for (int i = 1; i <= n;i++) {
		dfs(i);
	}
	for (int i = 1; i <= n;i++) {
		cout << i << ' ' << dp[i][0] << ' ' << dp[i][1] << endl;
	}
}

C++: #include<bits/stdc++.h>
#define N 105
using namespace std;
int n,u,k,v,e[N][N],cnt;
int ans1[N],ans2[N];
bool used[N];
 
void dfs(int x){
  if(used[x])return;
  used[x]=true;
  ans1[x]=cnt++;
  for(int i=0;i<n;i++)
    if(e[x][i])dfs(i);
  ans2[x]=cnt++;
}
 
int main(){
  cin>>n;
  for(int i=0;i<n;i++){
    cin>>u>>k;
    for(int j=0;j<k;j++)
      cin>>v,e[u-1][v-1]=1;
  }
  cnt=1;
  for(int i=0;i<n;i++){
    if(!used[i])dfs(i);
  }
  for(int i=0;i<n;i++){
    cout<<i+1<<' '<<ans1[i]<<' '<<ans2[i]<<endl;
  }
  return 0;
}

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

const int N = 100;
const int white = 0;
const int gray = 1;
const int black = 2;

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

//?????°dfs
void dfs_visit(int u){
    int v;
    color [u] = gray;
    d[u] = ++tt; //??????????¨????
    for ( v = 0; v < n ; ++v) {
        if (M[u][v] == 0)continue;
        if (color[v] == white){
            dfs_visit(v);
        }
    }
    color[u] = black;
    f[u] = ++tt; //?¨?????????????
}

void dfs(){
    int u;
    for (u = 0; u < n; ++u) {
        color[u] = white;
    }
    tt = 0;

    for (int u = 0; u < n ; ++u) {
        //????¨???????u????§??????¨????????±???????????¢?´¢
        if(color[u] == white) dfs_visit(u);
    }
    for (int u = 0; u < n ; ++u) {
        cout << u+1 << " " << d[u] << " " << f[u] << endl;
    }
}

int main(){
    int u,v,k;
    M[N][N] = {0};
    cin >> n;
    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<stdio.h>
#include<iostream>
#include<string>
using namespace std;

int n = 0;
int u = 0;
int k[101];
int v[101][101];
int Discover[101] = { 0 };
int End[101] = { 0 };
//int nx = 0;
int p = 0;
void dfs(int l) {
	int i;
	int j;
	if (!Discover[l]) {
		Discover[l] = ++p;

		for (i = 0; i < n + 1; i++) {
			if (v[l][i]) {
				dfs(v[l][i]);
			}
		}
		End[l] = ++p;
	}
}
int main()
{
	int i;
	int j;
	cin >> n;
	for (i = 0; i < n; i++) {
		cin >> u ;
		cin >> k[u];
		for (j = 0; j < k[u]; j++) {
			cin >> v[u][j];
		}
	}
	for (i = 1; i < n + 1; i++) {
		if (!Discover[i]) {
			dfs(i);
		}
	}
	for (i = 1; i < n + 1; i++) {
		cout << i << " " << Discover[i] << " " << End[i] << endl;
	}
}