Go: package main

/*
深さ優先探索
*/

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

func main() {
	scanner := makeScanner(8192)
	n := eGetInt(scanner)
	g := make([][]int, n+1)
	for i := 1; i < n+1; i++ {
		ints := eGetInts(scanner)
		num, vcount := ints[0], ints[1]
		g[i] = make([]int, vcount)
		for j := 0; j < vcount; j++ {
			g[num][j] = ints[j+2]
		}
	}
	hist := make([]struct{ d, f int }, n+1)
	t := 0
	var visit func(int)
	visit = func(num int) {
		if hist[num].d == 0 {
			stack := []int{}
			t++
			hist[num].d = t
			stack = append(stack, num)
			for len(stack) > 0 {
				// トップを訪問する
				top := stack[len(stack)-1]
				for i := 0; i < len(g[top]); i++ {
					if hist[g[top][i]].d == 0 {
						t++
						hist[g[top][i]].d = t
						stack = append(stack, g[top][i])
						goto endloop
					}
				}
				// 訪問場所がなくなったら
				// pop
				stack = stack[0 : len(stack)-1]
				t++
				hist[top].f = t
			endloop:
			}
		}
	}
	for i := 1; i < n+1; i++ {
		visit(i)
	}
	for i := 1; i < n+1; i++ {
		fmt.Println(i, hist[i].d, hist[i].f)
	}
}

////////////////////////////////////////////////////////////////////////////////
// ライブラリ
////////////////////////////////////////////////////////////////////////////////
func makeScanner(maxByte int) *bufio.Scanner {
	scanner := bufio.NewScanner(os.Stdin)
	scanner.Buffer(make([]uint8, 0, 8192), maxByte)
	return scanner
}
func makeWordScanner() *bufio.Scanner {
	scanner := makeScanner(8192)
	scanner.Split(bufio.ScanWords)
	return scanner
}
func eGetLine(r *bufio.Scanner) string {
	if r.Scan() {
		return r.Text()
	}
	err := r.Err()
	if err != nil {
		log.Fatal(err)
	}
	// EOF
	return ""
}
func eGetInt(r *bufio.Scanner) int {
	line := eGetLine(r)
	return eAtoi(line)
}
func eGetInt64(r *bufio.Scanner) int64 {
	line := eGetLine(r)
	return eAtoInt64(line)
}
func eGetFields(r *bufio.Scanner) []string {
	line := eGetLine(r)
	return strings.Fields(line)
}
func eGetInts(r *bufio.Scanner) []int {
	fields := eGetFields(r)
	ints := make([]int, len(fields))
	for i := 0; i < len(ints); i++ {
		ints[i] = eAtoi(fields[i])
	}
	return ints
}
func eGetInt64s(r *bufio.Scanner) []int64 {
	fields := eGetFields(r)
	ints := make([]int64, len(fields))
	for i := 0; i < len(ints); i++ {
		ints[i] = eAtoInt64(fields[i])
	}
	return ints
}
func eGetChars(r *bufio.Scanner) []string {
	line := eGetLine(r)
	return strings.Split(line, "")
}
func eAtoi(s string) int {
	n, err := strconv.Atoi(s)
	if err != nil {
		log.Fatal(err)
	}
	return n
}
func eAtoInt64(s string) int64 {
	n, err := strconv.ParseInt(s, 10, 64)
	if err != nil {
		log.Fatal(err)
	}
	return n
}

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

#define WHITE 0
#define GRAY 1
#define BLACK 2

int main ()
{
    int N;
    cin >> N;

    int M[N][N];
    int D[N], F[N], C[N];

    for (int i = 0; i < N; i++)
    {
        D[i] = 0;
        F[i] = 0;
        C[i] = WHITE;
        
        for (int j = 0; j < N; j++)
        {
            M[i][j] = 0;
        }
    }

    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] = 1;
        }
    }

/*
    for (int i = 0; i < N; i++)
    {
        for (int j = 0; j < N; j++)
        {
            if (j > 0)
                cout << " ";
            cout << M[i][j];
        }
        cout << endl;
    }
*/
    stack<int> *S = new stack<int>;

    int time = 0;

    S->push(0);
    C[0] = GRAY;
    D[0] = ++time;

    while (S->size() > 0)
    {
        int u = S->top();
        int v = -1;

        // next 
        for (int i = 0; i < N; i++)
        {
            int flag = M[u][i];

            if (flag == 1)
            {
                if (C[i] == WHITE)
                {
                    v = i;
                    break;
                }
            }
        }

        if (v != -1)
        {
            if (C[v] == WHITE)
            {
            C[v] = GRAY;
            D[v] = ++time;
            S->push(v);
            }
        }
        else
        {
            S->pop();
            C[u] = BLACK;
            F[u] = ++time;
        }
    }

    for (int i = 0; i < N; i++)
    {
        cout << i + 1 << " " << D[i] << " " << F[i] << endl;
    }
    return 0;
}

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


void solve(int);

typedef struct{
  int k;
  vector<int> ls;
  int f,d;
}node_t;

node_t node[101];
int t=0;

int main(){
  int n;
  int u;

  cin >> n;
  for(int i=0; i<n; i++){
    cin >> u; 
    cin >> node[u].k;
    node[u].ls.resize(node[u].k);
    node[u].d = node[u].f = -1;
    for(int j=0; j<node[u].k; j++){
      cin >> node[u].ls[j];
    }
    sort(node[u].ls.begin() , node[u].ls.end());
  }
 
  for(int i=0; i<n; i++)
    solve(i+1);

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

  return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;
struct Fast {
    Fast() {
        cin.tie(0);
        ios::sync_with_stdio(false);
        cout << fixed << setprecision(20);
    }
} fast;

void yes() {
    cout << "Yes" << endl;
    exit(0);
}
void no() {
    cout << "No" << endl;
    exit(0);
}
#define REP(i, n) for (long long i = 0; i < (n); i++)

long long modpow(long long m, long long n) {
    if (n == 0) return 1;
    if (n % 2 == 0) {
        long long t = modpow(m, n / 2);
        return t * t % 2019;
    } else {
        return modpow(m, n - 1) * m % 2019;
    }
}
long long n;
vector<bool> visited(100, false);
vector<int> t1(100);
vector<int> t2(100);
vector<vector<long long>> graph(100);
int ts = 1;
void dfs(int cur) {
    visited[cur] = true;
    t1[cur] = ts;
    ts++;
    for (int i = 0; i < graph[cur].size(); i++) {
        if (visited[graph[cur][i]] == false) {
            dfs(graph[cur][i]);
        }
    }
    t2[cur] = ts;
    ts++;
}
signed main() {
    cin >> n;
    for (long long i = 0; i < n; i++) {
        long long s, k;
        cin >> s >> k;
        for (int j = 0; j < k; j++) {
            int l;
            cin >> l;
            graph[s - 1].push_back(l - 1);
        }
    }
    REP(i, n) {
        if (!visited[i]) {
            dfs(i);
        }
    }
    REP(i, n) { cout << i + 1 << " " << t1[i] << " " << t2[i] << endl; }
}

C++: #include<stdio.h>
#include<stdlib.h>
#define N 102
#define white 0
#define gray 1
#define black 2

int n,color[N],d[N],f[N],S[N],top=0,t=0,nt[N],a[N][N];

void push(int x){
  if(top==N){
    printf("Stack overflow!\n");
    exit(2);
  }
  S[++top]=x;
}

int pop(void){
  if(top==0){
    printf("Stack is empty!\n");
    exit(3);
  }
  top--;
  return S[top+1];
}

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

void dfs(int r){
  int i;
  for(i=1;i<=n;i++) nt[i]=0;

  push(r);
  color[r]=gray;
  d[r]=++t;

  while(S[top]!=0){
    int u=S[top],v=next(u);

    if(v!=-1){
    if(color[v]==white){
      color[v]=gray;
      d[v]=++t;
      push(v);
    }
    }
    else {
      pop();
      color[u]=black;
      f[u]=++t;
    }
  }
}

void dfs_init(){
  int i,u;
  for(i=1;i<=n;i++){
    color[i]=white;
  }
  t=0;

  for(u=1;u<=n;u++){
    if(color[u]==white) dfs(u);
  }

}

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

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

  scanf("%d",&n);
  for(i=1;i<=n;i++){
    for(j=1;j<=n;j++){
      a[i][j]=0;
    }
  }

  for(i=1;i<=n;i++){
    scanf("%d%d",&u,&k);
    for(j=1;j<=k;j++){
      scanf("%d",&v);
      a[u][v]=1;
    }
  }

  dfs_init();
  print();


  return 0;
}