Go: package main

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

// I/O
type Scanner struct {
	sc *bufio.Scanner
}

func NewScanner() *Scanner {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)
	sc.Buffer(make([]byte, 1024), int(1e+9))
	return &Scanner{sc}
}

func (s *Scanner) nextStr() string {
	s.sc.Scan()
	return s.sc.Text()
}

func (s *Scanner) nextInt() int {
	i, e := strconv.Atoi(s.nextStr())
	if e != nil {
		panic(e)
	}
	return i
}

func (s *Scanner) nextFloat() float64 {
	f, e := strconv.ParseFloat(s.nextStr(), 64)
	if e != nil {
		panic(e)
	}
	return f
}

func (s *Scanner) nextRuneSlice() []rune {
	return []rune(s.nextStr())
}

func (s *Scanner) nextIntSlice(n int) []int {
	res := make([]int, n)
	for i := 0; i < n; i++ {
		res[i] = s.nextInt()
	}
	return res
}

func (s *Scanner) nextFloatSlice(n int) []float64 {
	res := make([]float64, n)
	for i := 0; i < n; i++ {
		res[i] = s.nextFloat()
	}
	return res
}

// Arithmetic
func max(nums ...int) int {
	m := nums[0]
	for _, i := range nums {
		if m < i {
			m = i
		}
	}
	return m
}

func min(nums ...int) int {
	m := nums[0]
	for _, i := range nums {
		if m > i {
			m = i
		}
	}
	return m
}

func abs(x int) int {
	if x > 0 {
		return x
	}
	return -x
}

func pow(x, y int) int {
	res := 1
	for i := 0; i < y; i++ {
		res *= x
	}
	return res
}

func ceil(a, b int) int {
	if a%b == 0 {
		return a / b
	} else {
		return a/b + 1
	}
}

// Sort
type RuneSlice []rune

func (a RuneSlice) Len() int           { return len(a) }
func (a RuneSlice) Less(i, j int) bool { return a[i] < a[j] }
func (a RuneSlice) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }

// Main
func main() {
	sc := NewScanner()
	wtr := bufio.NewWriter(os.Stdout)
	N := sc.nextInt()
	G := make([][]int, N)
	for i := 0; i < N; i++ {
		u, k := sc.nextInt()-1, sc.nextInt()
		for j := 0; j < k; j++ {
			G[u] = append(G[u], sc.nextInt()-1)
		}
	}
	ans := make([][2]int, N)
	time := 0
	found := make(map[int]bool)
	var dfs func(cur int)
	dfs = func(cur int) {
		time++
		ans[cur][0] = time
		found[cur] = true
		for i := 0; i < len(G[cur]); i++ {
			next := G[cur][i]
			if !found[next] {
				dfs(G[cur][i])
			}
		}
		time++
		ans[cur][1] = time
	}
	for i := 0; i < N; i++ {
		if !found[i] {
			dfs(i)
		}
	}

	for i := 0; i < N; i++ {
		fmt.Fprint(wtr, i+1)
		for j := 0; j < 2; j++ {
			fmt.Fprint(wtr, " ")
			fmt.Fprint(wtr, ans[i][j])
		}
		fmt.Fprintln(wtr)
	}
	wtr.Flush()
}

C++: #include <bits/stdc++.h>
#define rep(i, n) for(int i = 0; i < n; i++)
using namespace std;
typedef long long ll;

int n, t = 0;
vector<vector<int> > G(110);
pair<int, int> toki[110];
bool vis[110];

void dfs(int v)
{
    if(vis[v]) return;
    t++;
    toki[v].first = t;
    vis[v] = true;
    rep(i, G[v].size())
    {
        if(vis[G[v][i]]) continue;
        dfs(G[v][i]);
    }
    t++;
    toki[v].second = t;
    return;
}

int main(void)
{
    cin >> n;
    rep(i, n) vis[i] = false;
    rep(i, n)
    {
        int t, k;
        cin >> t >> k;
        t--;
        rep(j, k)
        {
            int v;
            cin >> v;
            v--;
            G[t].push_back(v);
        }
    }
    rep(i, n)
    {
        dfs(i);
    } 
    rep(i, n)
    {
        cout << i+1 << " " << toki[i].first << " " << toki[i].second << endl;
    }
    return 0;
}

C++: #include <iostream>
#include <stack>
using namespace std;
int d[101],f[101],G[101][101];
stack<int>s;
int n,t;
void dfs(int u)
{
    s.push(u);
    d[u]=t++;
    int i;
    while(!s.empty()){
        u=s.top();
        for(i=1;i<=n;i++)
        {
            if(G[u][i]==1 && d[i]==0)
            {
                s.push(i);
                d[i]=t++;
                //u=i;
                break;
            }
        }
        if(i>n)
        {
            f[s.top()]=t++;
            s.pop();
        }
    }
}
int main()
{
    int k,u,v;
    cin>>n;
    for(int i=1;i<=n;i++){
        d[i]=0;
        for(int j=1;j<=n;j++)
            G[i][j]=0;
    }
    for(int i=0;i<n;i++)
    {
        cin>>u>>k;
        for(int j=0;j<k;j++)
        {
            cin>>v;
            G[u][v]=1;
        }
    }
    t=1;
    for(int i=1;i<=n;i++)
    {
        if(d[i]==0)
            dfs(i);
    }
    for(int i=1;i<=n;i++)
    {
        cout<<i<<' '<<d[i]<<' '<<f[i]<<endl;
    }
    return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;

#define rep(i, m, n) for(int(i) = (int)(m); i < (int)(n); ++i)
#define rep2(i, m, n) for(int(i) = (int)(n)-1; i >= (int)(m); --i)
#define REP(i, n) rep(i, 0, n)
#define REP2(i, n) rep2(i, 0, n)
#define all(hoge) (hoge).begin(), (hoge).end()
#define en '\n'
using ll = long long;
using ull = unsigned long long;
using ld = long double;
template <class T>
using vec = vector<T>;
template <class T>
using vvec = vector<vec<T>>;
typedef pair<ll, ll> P;
constexpr long long INF = 1LL << 60;
constexpr int INF_INT = 1 << 25;
constexpr long long MOD = (ll)1e9 + 7;
//constexpr long long MOD = 998244353LL;
using ld = long double;
static const ld pi = 3.141592653589793L;
typedef vector<ll> Array;
typedef vector<Array> Matrix;

template <class T>
inline bool chmin(T &a, T b) {
    if(a > b) {
        a = b;
        return true;
    }
    return false;
}
template <class T>
inline bool chmax(T &a, T b) {
    if(a < b) {
        a = b;
        return true;
    }
    return false;
}

struct Edge {
    ll to, rev;
    long double cap;
    Edge(ll _to, long double _cap, ll _rev) {
        to = _to;
        cap = _cap;
        rev = _rev;
    }
};
using Edges = vector<Edge>;
using Graph = vector<Edges>;

void add_edge(Graph &G, ll from, ll to, long double cap, bool revFlag,
              long double revCap) {
    G[from].push_back(Edge(to, cap, (ll)G[to].size()));
    if(revFlag)
        G[to].push_back(Edge(from, revCap, (ll)G[from].size() - 1));
}

void solve() {
    ll n;
    cin >> n;
    Graph g(n);
    REP(i, n) {
        ll u, k;
        cin >> u >> k;
        u--;
        REP(j, k) {
            ll v;
            cin >> v;
            v--;
            add_edge(g, u, v, 1, false, 1);
        }
    }

    Array d(n, 0);
    Array f(n, 0);
    int id = 1;
    auto dfs = [&](auto &&self, int v) -> void {
        d[v] = id;
        id++;
        for(auto e : g[v]) {
            if(d[e.to])
                continue;
            self(self, e.to);
        }
        f[v] = id;
        id++;
    };
    REP(i, n) {
        if(d[i])
            continue;
        dfs(dfs, i);
    }
    REP(i, n) {
        cout << i + 1 << " " << d[i] << " " << f[i] << en;
    }
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);

    solve();

    /*
    ll t;
    cin >> t;
    REP(i, t) { solve();}
    */

    return 0;
}