Go: package main

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

//util
var sc = bufio.NewScanner(os.Stdin)

func nextStr() string {
	sc.Scan()
	return sc.Text()
}

func nextInt() int {
	sc.Scan()
	i, e := strconv.Atoi(sc.Text())
	if e != nil {
		panic(e)
	}
	return i
}

func printList(list []int) {
	n := len(list)
	buf := bufio.NewWriter(os.Stdout)
	for _, v := range list[0 : n-1] {
		buf.Write([]byte(fmt.Sprintf("%d ", v)))
	}
	buf.Write([]byte(fmt.Sprintf("%d\n", list[n-1])))
	buf.Flush()
}

func max(a, b int) int {
	if a > b {
		return a
	} else {
		return b
	}
}

func min(a, b int) int {
	if a > b {
		return b
	} else {
		return a
	}
}

//solve

const MAX = 100
const WHITE = 0
const GRAY = 1
const BLACK = 2

var time, n int

//隣接行列
var M [MAX][MAX]int

//d[i]: 最初にiを訪問した時刻。発見時刻
//f[i]: iの隣接リストを訪問し終えた時刻。完了時刻
var color, d, f [MAX]int

func dfs_visit(u int) {
	color[u] = GRAY
	time++
	d[u] = time
	//隣接を調べる
	for v := 0; v < n; v++ {
		if M[u][v] == 0 {
			continue
		}
		//隣接するvが、未訪問だった場合
		if color[v] == WHITE {
			dfs_visit(v)
		}
	}
	//訪問完了処理
	color[u] = BLACK
	time++
	f[u] = time
	//訪問完了
}

func dfs() {
	//初期化
	for u := 0; u < n; u++ {
		color[u] = WHITE
	}
	time = 0

	//未訪問のuを始点として、深さ優先探索
	for u := 0; u < n; u++ {

		if color[u] == WHITE {
			dfs_visit(u)
		}
	}

	for u := 0; u < n; u++ {
		fmt.Println(u+1, d[u], f[u])
	}
}

func main() {
	sc.Split(bufio.ScanWords)
	n = nextInt()
	for i := 0; i < n; i++ {
		u, k := nextInt(), nextInt()
		M[u-1][u-1] = 0

		//fmt.Println(u, k)
		if k > 0 {
			for j := 0; j < k; j++ {

				v := nextInt()
				M[u-1][v-1] = 1

			}
		}

	}

	dfs()

}

C++: #include <iostream>
#include <array>
#include <algorithm>
#include <stack>

const int nmax = 105;
const int NIL = -1;

int n, t;
// state of vertex
// 0: not visited
// 1: visited
// 2: complete search from the vertex
std::array<int, nmax> color, d, f;

std::array<std::array<int, nmax>, nmax> adj;


void dfs_1v(int v)
{
  d[v] = ++t;
  color[v] = 1;

  for (int j=0; j<n; ++j)
    {
      if (adj[v][j] == 1 && color[j] ==0)
        {
          dfs_1v(j);
        }
    }
  f[v] = ++t;
  color[v] = 2;
}

void dfs()
{
  t = 0;
  for (int i=0; i<n; ++i)
    {
      if (color[i] != 2)
        dfs_1v(i);
    }
}

int main ()
{
  std::cin >> n;

  color.fill(0);
  std::for_each(adj.begin(), adj.end(), [](auto x){x.fill(0);});
  for (int i=0; i<n; ++i)
    {
      int u, k;
      std::cin >> u >> k;
      for (int j=0; j<k; ++j)
        {
          int v;
          std::cin >> v;
          adj[u-1][v-1] = 1;
        }
    }

  dfs();

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

}

C++: #include <bits/stdc++.h>

using namespace std;
int t;

void dfs(vector<vector<bool> >& A, vector<vector<int> >& B, int s, int n){
    for(int i = 0; i < n; i++){
        if(i == 0){
            if(B[s][1] == 0){
                B[s][1] = t;
                t++;
            }
        }
        if(A[s][i] == true){
            A[s][i] = false;
            dfs(A, B, i, n);
        }
        if(i == n-1){
            if(B[s][2] == 0){
                B[s][2] = t;
                t++;
            }
        }
    }
}

int main(void){

    //??£??\??????????????£??\???????????????
    int n, k;

    cin >> n;
    vector<vector<bool> > A(n, vector<bool>(n, false));
    for(int i = 0; i < n; i++){
        cin >> k >> k;
        for(int j = 0; j < k; j++){
            int input;
            cin >> input;
            A[i][input-1] = true;
        }
    }

   

    vector<vector<int> > B(n, vector<int>(3, false));
    for(int i = 0; i < n; i++){
        B[i][0] = i + 1;
    }

    t = 1;
    for(int k = 0; k < n; k++){
        if(B[k][1] == 0) dfs(A, B, k, n);
    }
    

    //??????
    for(int i = 0; i < n; i++){
        for(int j = 0; j < 3; j++){
            if(j != 2) cout << B[i][j] << " ";
            else cout << A[i][j];
        }
        cout << endl;
    }
    return 0;
}

C++: #include <stdio.h>
#include <iostream>
#include <stack>
#include <string>
using namespace std;

#define NUM 100
int node_num;
int V[NUM + 1][NUM + 1];
int d[NUM + 1];
int f[NUM + 1];
string color[NUM + 1];
int t;
int pos;
stack<int> s;

void createAdj(int n){
    for(int j = 0; j <= n; j++){
        if(j == 0){
            V[0][j] = 0;
        }
        V[0][j] = 1;
    }

    for(int i = 1; i < NUM; i++){
        for(int j = 1; j < NUM; j++){
            V[i][j] = 0;
        }
    }

    for(int i = 0; i < n; i++){
        int num1;
        scanf("%d", &num1);

        int n;
        scanf("%d", &n);

        int num2;
        for(int j = 0; j < n; j++){
            scanf("%d", &num2);
            V[num1][num2] = 1;
        }
    }
}

int search(int n){
    for(int i = 1; i <= node_num; i++) {
        if(V[n][i] == 1 && color[i] == "white")
            return i;
    }
    return -1;
}

void dfs_init(){
    t = 0;
    for(int i = 0; i < NUM; i++){
        color[i] = "white";
    }
}

void dfs(){
    s.push(0);
    pos = 0;
    color[0] = "grey";
    d[0] = t;

    while(s.size()){
        int u = s.top();
        int next_node = search(u);
        if(next_node != -1){
            pos = next_node;
            s.push(next_node);
            pos = next_node;
            t++;
            color[next_node] = "grey";
            d[next_node] = t;
        }else{
            s.pop();
            color[u] = "black";
            t++;
            f[u] = t;
        }
    }
}

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

int main(void){
    scanf("%d", &node_num);
    createAdj(node_num);

    dfs_init();
    dfs();

    print();
}

C++: #include <cstdio>
#include <cstdlib>
#include <iostream>
#include <algorithm>
#include <cstring>
using namespace std;

bool A[110][110];
int flag[110],in[110],out[110];
int now=1,n;

void dfs(int u){
	flag[u]=1;
	in[u]=now++;
	for(int i=1;i<=n;i++){
		if(flag[i]==0 && A[i][u]==true){
			dfs(i);
		}
	}
	out[u]=now++;
	return ;
}

int main(){
	int a,b,c;
	cin>>n;
	for(int i=1;i<=n;i++){
			for(int j=1;j<=n;j++){
				A[i][j]=false;
		}
	}
	for(int i=1;i<=n;i++){
		cin>>a>>b;
		for(int j=1;j<=b;j++){
			cin>>c;
			A[a][c]=true;
			A[c][a]=true;
		}
	}
	for(int i=1;i<=n;i++){
		if(flag[i]==0) dfs(i);
	}
	for(int i=1;i<=n;i++){
		cout<<i<<" "<<in[i]<<" "<<out[i]<<endl;
	}
	return 0;
}

C++: #include<iostream>
#include<stdio.h>

using namespace std;
int d[101];
int f[101];
int n;
int M[101][101];
int t;
void DFS(int v) {
	t = t + 1;
	d[v] = t;
	for (int j = 1; j < n + 1; j++) {
		if (M[v][j] == 1) {
			if (d[j] == 0) {
				DFS(j);

			}
		}
	}
	t = t + 1;
	f[v] = t;

}

int main() {
	int  u, k, v;//頂点数、頂点の番号、出次数、隣接する頂点の番号
	t = 0;

	cin >> n;



	//初期化
	for (int i = 0; i < 101; i++) {
		d[i] = 0;
		f[i] = 0;
		for (int j = 0; j < 101; j++) {
			M[i][j] = 0;

		}
	}

	for (int i = 0; i < n; i++) {
		cin >> u >> k;
		for (int j = 0; j < k; j++) {
			cin >> v;
			M[u][v] = 1;
		}
	}


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

	return 0;
}