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 <stack>
using namespace std;

int n;
int g[101][101];
char c[101];
int visit[101];
int finish[101];
int main() {
    cin >> n;
    for (int i = 1; i <= n; ++i) {
        int u, k;
        cin >> u >> k;
        for (int j = 0; j < k; ++j) {
            int v;
            cin >> v;
            g[u][v] = 1;
        }

    }

   stack<int> s;
    for (int l = 1; l <= n; ++l) {
        c[l] = 'w';

    }
    int time = 0;
    int start = 0;
    int v;
    while(true) {
        start++;
        if(start == n) break;
        if(c[start] == 'w') {
            time++;
            s.push(start);
            c[start] = 'g';
            visit[start] = time;
            while (s.size() != 0) {
                time++;
                v = s.top();
                int next = -1;
                for (int i = 1; i <= n ; ++i) {
                    if(i == v) {
                        continue;
                    }
                    if(g[v][i] && c[i] == 'w') {
                        next = i;
                        break;
                    }
                }
                if(next == -1) {
                    c[v] = 'b';
                    finish[v] = time;
                    s.pop();
                } else {
                    c[next] = 'g';
                    visit[next] = time;
                    s.push(next);
                }
            }
        }
    }

    for (int m = 1; m <= n; ++m) {
        cout << m << " " << visit[m ] << " " << finish[m] << endl;

    }



    return 0;
}

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

int dfs_visit(int u)
{
    int v;
    color[u] = GRAY;
    d[u] = ++tt;
    for (int v = 0; v < n; v++)
    {
        if (M[u][v] == 0)
        {
            continue;
        }
        if (color[v] == WHITE)
        {
            dfs_visit(v);
        }
    }
    color[u] = BLACK;
    f[u] = ++tt;
}

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

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

typedef struct timestamp {
        int d, f;
} timestamp;

const int N = 100;
bool graph[N][N] {{false}};
timestamp ts[N];
int time = 0;

void search(int n, int cur) {
        ts[cur].d = ++time;
        for (int i = 0; i < n; i++) {
                if (graph[cur][i] && !ts[i].d) {
                        search(n, i);
                }
        }
        ts[cur].f = ++time;
}

int main() {
        int n, u, k, v;
        for (int i = 0; i < N; i++) {
                ts[i].d = ts[i].f = 0;
        }

        scanf("%d", &n);
        for (int i = 0; i < n; i++) {
                scanf("%d %d", &u, &k);
                for (int j = 0; j < k; j++) {
                        scanf("%d", &v);
                        graph[u-1][v-1] = true;
                }
        }
        int cur = 0;
        search(n, cur);
        for (int i = 0; i < n; i++) {
                printf("%d %d %d\n", i+1, ts[i].d, ts[i].f);
        }

        return 0;
}

C++: #include <vector>
#include <cmath>
#include <iostream>
#include <algorithm>

int n;
int time_count = 0;
std::vector<std::pair<int, int>> times;
std::vector<std::vector<int>> vec;

void dfs(int id) {
    if (times[id-1].first == -1 && times[id-1].second == -1) {
        times[id-1].first = ++time_count; 
        for (int i = 1; i <= n; i++) {
            if (vec[id][i] == 1) {
                dfs(i);
            }
        }
        times[id-1].second = ++time_count;
    }
}

int main() {
    std::cin >> n;
    vec.assign(n+1, std::vector<int>(n+1, 0));
    for (int i = 0; i < n; i++) {
        times.push_back(std::make_pair(-1, -1));
    }
    for (int i = 0; i < n; i++) {
        int id, num, d;
        std::cin >> id >> num;
        for (int p = 0; p < num; p++) {
            std::cin >> d;
            vec[id][d] = 1;
        }
    }
    dfs(1);
    
    for (int i = 0; i < n; i++) {
        std::cout << i+1 << " " << times[i].first << " " << times[i].second << std::endl;
    }
}

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

int d[100];
int f[100];
int map[100][100];
int tim;
int n;
stack<int> s;
void visit(int);

int main(){
	tim=0;
	int i,j,k,u,v;
	for(i=0;i<100;i++) d[i]=-1; //?????¢??\
	for(i=0;i<100;i++) f[i]=-1;
	cin >> n;
	for(i=0;i<n;i++){
		for(j=0;j<n;j++){
			map[i][j]=-1;
		}
	}
	for(i=0;i<n;i++){
		cin>>u>>k;
		for(j=0;j<k;j++){
			cin>>v;
			map[u-1][v-1]=1; //?????????????????????????????????????????????
		}
	}
	visit(0); //????????¢?????¢?´¢
	for(i=0;i<n;i++) cout<< i+1 <<" "<<d[i]<<" "<<f[i]<<endl;
	return 0;
}

void visit(int a){
	s.push(a); //?????¨??°
	if(d[a]==-1){
		d[a]=++tim;
	}
	for(int i=0;i<n;i++){
		if(map[a][i]==1 && d[i]==-1){ //?????¢?´¢
			visit(i);
		}
	}
	s.pop();
	f[a]=++tim;
}

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

int a[100][100];
int n,p,q,r;
int T[100],F[100];
int Time = 0;
void dfs(int cur) {
	T[cur] = Time;
	Time += 1;
	for (int dst=0; dst < n; ++dst) {
		if(a[cur][dst] == 1 && T[dst] == -1) {
			dfs(dst);
		}
	}
	F[cur] = Time;
	Time += 1;
}

int main() {
	cin >> n;
	for (int i=0; i<n; ++i) {
		cin >> p >> q;
		T[i] = -1;
		for (int j=0; j<q; ++j) {
			cin >> r;
			a[p-1][r-1] = 1;
		}
	}
	dfs(0);
	for (int i=0; i<n-1; ++i) {
		cout << i+1 << " " << T[i]+1 << " " << F[i]+1 << endl;
}
cout << n << " " << T[n-1]+1 << " " << F[n-1]+1
}