Go: package main

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

func main() {
	scn := bufio.NewScanner(os.Stdin)
	scn.Split(bufio.ScanWords)
	nextInt := func() int { scn.Scan(); r, _ := strconv.Atoi(scn.Text()); return r }
	w := bufio.NewWriter(os.Stdout)

	n := nextInt()
	vecs := make([][]int, n)
	for i := 0; i < n; i++ {
		u := nextInt()
		k := nextInt()
		for j := 0; j < k; j++ {
			vecs[u-1] = append(vecs[u-1], nextInt()-1)
		}
	}

	ds := make([]int, n)
	fs := make([]int, n)
	founds := make([]bool, n)
	t := 0
	for i := range founds {
		if !founds[i] {
			t = dfs(vecs, ds, fs, founds, i, t)
		}
	}

	for i := 0; i < n; i++ {
		fmt.Fprintln(w, i+1, ds[i], fs[i])
	}

	w.Flush()
}

func dfs(vecs [][]int, ds, fs []int, founds []bool, i, t int) (time int) {
	t++
	ds[i] = t
	founds[i] = true
	for _, v := range vecs[i] {
		if !founds[v] {
			t = dfs(vecs, ds, fs, founds, v, t)
		}
	}
	t++
	fs[i] = t

	return t
}

C++: // ALDS1_11_B
#include <iostream>
#include <vector>
using namespace std;

void DFS(vector<vector<int> > A, vector<int> &d, vector<int> &f, vector<int> &visit, int &t, int v){
	
	visit[v] = 1;
	d[v] = t++;

	for(int i=0;i<A[v].size();i++)
		if((A[v][i] == 1) && (visit[i] == 0))
			DFS(A, d, f, visit, t, i);

	f[v] = t++;
}

int main(){
	int n, u, k, t=1;
	vector<vector<int> > A;
	vector<int> d, f, visit;

	cin>>n;
	A.resize(n);
	d.resize(n);
	f.resize(n);
	for(int i=0;i<n;i++){
		A[i].resize(n);
		visit.push_back(0);
	}

	for(int i=0;i<n;i++)
		for(int j=0;j<n;j++)
			A[i][j] = 0;

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

	DFS(A, d, f, visit, t, 0);
	for(int i=0;i<n;i++)
		cout<<i+1<<" "<<d[i]<<" "<<f[i]<<endl;

	return 0;
}

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

int r[101][101];
int d[101], f[101], num, visit[101], p=0;

void dfs(int n){
    if(!visit[n]){
        visit[n]++;
        d[n] = ++p;
        for(int i=1; i<num+1; i++)
            if(r[n][i]) dfs(i);
        f[n] = ++p;
    }
}

int main(void){
    int u, k, v;
    cin >> num;
    for(int i=0; i<num; i++){
        cin >> u >> k;
        for(int j=0; j<k; j++){
            cin >> v;
            r[u][v]++;
        }
    }
    for(int i=1; i<num+1; i++){
        if(!visit[i]) dfs(i);
    }
    for(int i=1; i<num+1; i++)
        cout << i << " " << d[i] << " " << f[i] << endl;
}

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

using namespace std;

int N,k[1000];
int v[1000][1000];
int found[1000] = {0},ended[1000] = {0};
int keep;
int checking=0;

void dfs(int cur);

int main() {
	cin >> N;
	for(int i=1;i<N+1;i++) {
		cin >> keep >> k[i];
		for(int j=1;j<k[i]+1;j++) {
			cin >> v[i][j];

		}
	}
	dfs(1);
	
	for(int i=1;i<N+1;i++) {
		cout << i << " " << found[i] << " " << ended[i] << endl;
	}
	

}

void dfs(int cur) {
	
	if(!found[cur]) {
		checking++;
		//cerr << "visiting: " << cur << " " << "time: " << checking << endl;
		found[cur] = checking;
	}
	for(int dst=1;dst<N+1;dst++) {
		bool flag = false;
		for(int i=1;i<k[cur]+1;i++) {
			if(v[cur][i] == dst) flag = true;
		}
		if(flag) dfs(dst);
	}
	if(!ended[cur]) {
		checking++;
		//cerr << "ended: " << cur << " " << "time: " << checking << endl;
		ended[cur] = checking;
	}
}

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

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

    std::vector<std::vector<unsigned long>> edges(n);
    for(auto&& i : edges){
        unsigned long u;
        std::cin >> u;
        unsigned long k;
        std::cin >> k;
        i = std::vector<unsigned long>(k);
        for(auto&& j : i){
            std::cin >> j;
            --j;
        }
    }

    std::vector<unsigned long> d(n), f(n);

    [dfs_impl = [&edges, &d, &f](auto func, unsigned long now, unsigned long& t) -> void {
        d[now] = ++t;
        for(const auto& i : edges[now])if(!d[i])func(func, i, t);
        f[now] = ++t;
    }, &n, &d]{
        unsigned long t{0};
        for(unsigned long i{0}; i < n; ++i)if(!d[i])dfs_impl(dfs_impl, i, t);
    }();

    for(unsigned long i{0}; i < n; ++i)std::cout << i + 1 << " " << d[i] << " " << f[i] << std::endl;

    return 0;
}