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>
#include <vector>

using namespace std;

int n;
int G[105][105];
vector<int> d(105,0),f(105,0);
int t=1;

void dfs(int x){
    if(d[x]==0) d[x]=t;
    for (int j=1; j<=n; j++) {
        if (G[x-1][j-1]==1 and d[j]==0) {
            t++;//5
            dfs(j);
        }
    }
    t++;
    if(f[x]==0) f[x]=t;
}


int main(){
    cin >> n;
    for (int i =0; i<n; i++) {
        for (int j =0; j<n; j++) {
            G[i][j] = 0;
        }
    }
    for (int i=0;i<n;i++) {
        int p,m;
        cin >>p >> m;
        for (int j=0; j<m; j++) {
            int q;
            cin >> q;
            G[p-1][q-1]=1;
        }
    }
    dfs(1);
    for (int i=1; i<=n; i++) {
        cout << i << " "<<d[i]<<" "<<f[i]<<endl;
    }
}

C++: #include <iostream>
#include <vector>
#define WHITE 0
#define GRAY 1
#define BLACK 2
using namespace std;

int N, k, tt=0, starttime[100], stoptime[100], color[100]={0};
vector<int> E[100];

void dfsfunc(int node){
    //cout << node << " OKdfsfunc" << endl;
    tt++;
    starttime[node] = tt;
    color[node] = GRAY;
    for(int i=0;i<E[node].size();i++){
        if(color[E[node][i]]==WHITE){
            dfsfunc(E[node][i]);
        }
    }
    tt++;
    stoptime[node] = tt;
    color[node] = BLACK;
}

void dfs(){
    for(int node=0;node<N;node++){
        if(color[node]==WHITE) dfsfunc(node);
    }
    //cout << "OK" << endl;
}

int main(){
    cin >> N;
    for(int i=0;i<N;i++) {
        cin >> k;
        cin >> k;
        //cout << "OK" << endl;
        for(int j=0;j<k;j++) {
            int node;
            cin >> node;
            node--;
            E[i].push_back(node);
        }
    }
    //cout << "OK" << endl;
    dfs();
    for(int i=0;i<N;i++) cout << i+1 << " " << starttime[i] << " " << stoptime[i] << endl; 
}

C++: #include <iostream>
#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;
//?????\??????
int M[N][N];
//??°?????¶???????¢????
int color[N];
//??\??¶????????°??¶???
int d[N];
//??\??¶???????????¶???
int f[N];
//??¶???
int tt;
//???????????????????????????????????????
//?????¨?????????????????¨????????\??????????????????
int nt[N];

//????????????????????????u?????????v
int next(int u){
    for(int v=nt[u];v<n;v++){
        nt[u]=v+1;
        if(M[u][v]&&color[v]==WHITE)
            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){
            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++)
        nt[i]=0,color[i]=WHITE;
    tt=0;

    //??\????????????u?????????????????±?????????????´¢
    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();
}

C++: #include "bits/stdc++.h"

using namespace std;

void dfs(int curr, int& ts, const vector<set<int> >& graph
        , vector<int>& d, vector<int>& f) {

    ++ts;
    d[curr] = ts;
    const set<int>& nextNodes = graph[curr];
    for (int n : nextNodes) {
        if (d[n] > 0) {
            continue;
        }
        dfs(n, ts, graph, d, f);
    }
    ++ts;
    f[curr] = ts;
}

void Main() {
    int n;
    cin >> n;
    vector<set<int> > graph(n, set<int>());
    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;
            graph[u].insert(v);
        }
    }

    vector<int> d(n, -1);
    vector<int> f(n, -1);
    int timestamp = 0;
    for (int i = 0; i < n; ++i) {
        if (d[i] < 0) {
            dfs(i, timestamp, graph, d, f);
        }
    }
    for (int i = 0; i < n; ++i) {
        cout << (i + 1) << " " << d[i] << " " << f[i] << endl;
    }
}

int main() {
    std::cout << std::fixed << std::setprecision(15);
    Main();
    return 0;
}