Go: package main

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

// repr state of visited node
// WHITE yet visit
// GEAY  visiting
// BLACK visited
const (
	WHITE int = iota
	GRAY
	BLACK
)

type dfsGraph struct {
	g      [][]int
	colors []int
	stime  []int // Start time of visiting node
	ftime  []int // Finish time of visiting node
}

var time int

func makeAdjList() [][]int {
	var n int
	fmt.Scanf("%d", &n)

	adj := make([][]int, n)
	for i := 0; i < n; i++ {
		adj[i] = make([]int, n)
	}

	sc := bufio.NewScanner(os.Stdin)
	for i := 0; i < n; i++ {
		sc.Scan()
		nodeInfo := strings.Split(sc.Text(), " ")
		outDegree, _ := strconv.Atoi(nodeInfo[1])

		if outDegree > 0 {
			for k := 0; k < outDegree; k++ {
				j, _ := strconv.Atoi(nodeInfo[k+2])
				j-- // convert 1 based to 0 based
				adj[i][j] = 1
			}
		}
	}

	return adj
}

func (dg dfsGraph) dfsVisit(u int) {
	// 頂点uを訪問中に設定
	dg.colors[u] = GRAY
	time++
	dg.stime[u] = time

	// uの隣接nodeを訪問
	for v := 0; v < len(dg.g); v++ {
		if dg.g[u][v] == 0 {
			continue // 辺がなければスキップ
		}

		// vが未訪問なら訪問
		if dg.colors[v] == WHITE {
			dg.dfsVisit(v)
		}
	}

	// 頂点uを訪問済みに設定
	dg.colors[u] = BLACK
	time++
	dg.ftime[u] = time
}

func (dg dfsGraph) dfs() {
	for i := 0; i < len(dg.g); i++ {
		if dg.colors[i] == WHITE {
			dg.dfsVisit(i)
		}
	}
}

func (dg dfsGraph) printDfsTime() {
	for i := 0; i < len(dg.g); i++ {
		fmt.Printf("%d %d %d\n", i+1, dg.stime[i], dg.ftime[i])
	}
}

func main() {
	adj := makeAdjList()
	colors := make([]int, len(adj))
	stime := make([]int, len(adj))
	ftime := make([]int, len(adj))
	graph := dfsGraph{adj, colors, stime, ftime}
	graph.dfs()
	graph.printDfsTime()
}

C++: #include <iostream>
using namespace std;
int g[101][102],ch[101][2]={0},kh;

int dfs(int k,int n){
  ch[n][0]=k;
  //cout<<k<<n<<"<--"<<endl;/////////
  for(int i=1;i<=g[n][0];i++){
    if(ch[g[n][i]][0]==0){
      k=dfs(k+1,g[n][i]);
    }
  }
  ch[n][1]=k+1;
  kh=k+1;
  return k+1;
}

int main(){
  int a,b,c,d;
  cin>>a;
  for(int i=0;i<a;i++){
    cin>>b>>c;
    g[b][0]=c;
    for(int j=1;j<=c;j++){
      cin>>d;
      g[b][j]=d;
    }
  }
  kh=0;
  for(int i=1;i<=a;i++){
    if(ch[i][0]==0){
      //cout<<i<<"<--"<<endl;////////
      dfs(kh+1,i);
    }
  }
  
  for(int i=1;i<=a;i++){
    cout<<i<<" "<<ch[i][0]<<" "<<ch[i][1]<<endl;
    
  }
  return 0;
}

C++: #include <iostream>
using namespace std;
struct Node{
  int u;
  int k;
  int v[99];

  int start;
  int finish;
};

int deep(Node nod[],int x,int count){
  if(nod[x].start)
    return count;

  nod[x].start=(++count);
  cout << nod[x].u << " " << count << endl;
  for(int i=0; i<nod[x].k; i++)
    count = deep(nod,nod[x].v[i]-1,count);

  nod[x].finish= (++count);
  return count;
}

int main(){
  int n,count=0;
  Node nod[100];

  cin >> n;
  for(int i=0; i<n; i++){
    cin >> nod[i].u >> nod[i].k;
    
    for(int j=0; j<nod[i].k; j++)
      cin >> nod[i].v[j];
    
    nod[i].start=0;
    nod[i].finish=0;
  }

  for(int i=0; i<n; i++)
    count = deep(nod,i,count);
  
  for(int i=0; i<n; i++){
    cout << nod[i].u << " " << nod[i].start << " " << nod[i].finish << endl;
  }
}

C++: #include <iostream>
#include <vector>
using namespace std;
typedef vector <int> vi;
typedef vector <vi> vvi;
int counter=0;

int addedge(vvi &graph, int y, int x, int val=1){
	graph[y][x] = val;
	return val;
}

int make_graph(vvi &graph, vvi &stamp){
	int n1=graph.size(), n2, row, col;

	for (int j=0; j<n1; j++){
		cin>>row;
		cin>>n2;
		for (int i=0; i<n2; i++){
			cin>>col;
			addedge(graph, row-1, col-1);
		}
		stamp[j][0] = -1;
	}
	return 0;
}

int Depth_First_Search(vvi &graph, vvi &stamp, int key=0){
	if (stamp[key][0] != -1) return 0;
	stamp[key][0] = ++counter;
	for (int i=0; i<int(graph[0].size()); i++){
		if (graph[key][i]==1 && stamp[i][0]==-1){
			Depth_First_Search(graph, stamp, i);
		}
	}
	stamp[key][1] = ++counter;
	return 0;
}

int resultout(vvi &stamp){
	for (int i=0; i<int(stamp.size()); i++){
		cout<<i+1<<" "<<stamp[i][0]<<" "<<stamp[i][1]<<endl;
	}
	return 0;
}

int main(void){

	int n, row;
	cin>>n;
	vvi G(n, vi(n)), stamp(n, vi(2));

	make_graph(G, stamp);

	Depth_First_Search(G, stamp);

	resultout(stamp);

	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) {
    if (d[id] != 0) {
        return;
    }
    ++t;
    d[id] = t;

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

    ++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;
        }
    }

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

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

    return 0;
}