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<string>
#include<algorithm>
#include<stack>
using namespace std;

static const int N = 100;
static const int WHITE = 0;
static const int GRAY = 1;
static const int BLACK = 2;

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

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

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

  stack<int> S;
  S.push(r);
  color[r] = GRAY;
  d[r] = ++tt;

  while(!S.empty()){
    int u = S.top();
    int v = next(u);
    if(v != -1){
      if(color[v] == WHITE){
        color[v] = GRAY;
        d[v] = ++tt;
        S.push(v);
      }
    }else{
      S.pop();
      color[u] = BLACK;
      f[u] = ++tt;
    }
  }
}

void dfs(){
  for(int i=0;i<n;i++){
    color[i] = WHITE;
    nt[i] = 0;
  }
  tt = 0;

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

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

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

  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 <iostream>
#include <stack>
using namespace std;

#define MAX 100

stack<int> G;
int Graph[MAX+1][MAX+1];
int result[MAX+1][2];
int n;
int cnt = 0;

void dfs(int idx) {
    bool bl = false;
    for(int i=1; i<=n; i++) {
        //もし一つでも残っているノードがあればpushする
        if(Graph[idx][i]==1) {
            for(int j=1; j<=n; j++) {
                Graph[j][i] = 0;
            }
            //cout << "push: " << i << endl;
            cnt++;
            result[i][0] = cnt;
            G.push(i);
            dfs(i);
            bl = true;
        }
    }
    //一つも残っていなかったらpopする
    if(bl==false) {
        //cout << "pop: " << G.top() << endl;
        cnt++;
        result[G.top()][1] = cnt;
        G.pop();
        if(G.empty()) {
            return;
        }
        else {
            dfs(G.top());
        }
    }
}

int main() {
    int idx, g_num, a;

    cin >>n;
    for(int i=0; i<n; i++) {
        cin >> idx >> g_num;
        for(int j=0; j<n; j++) {
            Graph[idx][j] = 0;
        }
        for(int j=0; j<g_num; j++) {
            cin >> a;
            Graph[idx][a] = 1;
        }
    }
    G.push(1);
    cnt++;
    result[1][0] = cnt;
    //cout << "push: " << 1 << endl;
    dfs(1);

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

    return 0;
}

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

int n, u;
int k[101], b[101], d[101], f[101];
int a[101][101];
int t = 1;

void dfs(int v){
    d[v] = t;
    t++;
    b[v]++;
    for(int l=0; l<k[v]; l++){
        if(b[a[v][l]] == 0){
            dfs(a[v][l]);
        }
    }
    f[v] = t;
    t++;
}


int main() {
    ios::sync_with_stdio(false);
    cin >> n;
    for(int i=0; i<n; i++){
        cin >> u;
        cin >> k[u];
        for(int j=0; j<k[u]; j++){
            cin >> a[u][j];
        }
    }
    for(int v=1; v<=n; v++){
        if(b[v] == 0){
            dfs(v);
        }
        cout << v << " " << d[v] << " " << f[v] << endl;
    }
    return 0;
}

C++: #include<iostream>

int main(){

  int n,a;
  std::cin>>n;

  int Adj[100][100],adj[100][100]={0},find[100][2],back[100],depth[100]={0},endflag[100]={0},flag;
  int u[n],k[n],kcou=0,timenow=0,v,pred,prev,firstv;
  for(int i=0;i<n;i++){
    std::cin>>u[i];
    std::cin>>k[i];
    for(int j=0;j<k[i];j++){
      std::cin>>Adj[i][j];
    }
  }
	
	/*
  for(int i=0;i<n;i++){
    for(int j=0;j<n;j++){
    	std::cout<<Adj[i][j]<<" ";
    }
  	std::cout<<"\n";
  }*/
	
	v=0;
	firstv=0;
	while(timenow<n*2){
		flag=0;
		if(find[firstv][0]!=NULL&&find[firstv][1]!=NULL){
			for(int i=0;i<n;i++){
				if(find[i][0]==NULL){
					//std::cout<<i<<"\n";
					firstv=i;
					v=i;
					break;
				}
			}
		}
		//std::cout<<v;
		///std::cout<<find[v][0]<<" "<<find[v][1];
		if(find[v][0]==NULL){
			timenow++;
			find[v][0]=timenow;
			flag=1;
			//std::cout<<flag<<" 1";
		}else if(find[v][1]==NULL){
			if(endflag[v]==1){
				timenow++;
				find[v][1]=timenow;
				flag=2;
			}
			//std::cout<<flag<<" 2";
		}else{
			v=back[v];
			flag=3;
			//std::cout<<flag<<" 0";
		}

		if(flag==0){
			pred=depth[v];
			depth[v]++;
			prev=v;
			v=Adj[v][pred]-1;
			back[v]=prev;
			//std::cout<<flag<<"\n";
		}else if(flag==1){
			if(endflag[v]==0){
				if(Adj[v][depth[v]]-1!=v&&Adj[v][depth[v]]-1!=firstv){
					pred=depth[v];
					depth[v]++;
					prev=v;
					v=Adj[v][pred]-1;
					back[v]=prev;
					//std::cout<<v<<"\n";
				}else{
					pred=depth[v];
					depth[v]++;
				}
			}
		}else if(flag==2){
			v=back[v];
			//std::cout<<flag<<"\n";
		}
		if(depth[v]>k[v]-1){
			endflag[v]=1;
		}
		
	}
	
	
	
	
  for(int i=0;i<n;i++){
     std::cout<<i+1<<" "<<find[i][0]<<" ";
     std::cout<<find[i][1]<<"\n";
    //std::cout<<"\n";
  }

  return 0;
}