Go: package main

import (
	"bufio"
	"bytes"
	"fmt"
	"io"
	"os"
	"strconv"
	"strings"
)

const N = 100

const (
	WHITE = iota
	GRAY
	BLACK
)

type Graph struct {
	M               [N][N]int
	color, d, f, nt [N]int
	tt              int
}

func (g *Graph) next(u, n int) int {
	for v := g.nt[u]; v < n; v++ {
		g.nt[u] = v + 1
		if g.M[u][v] != 0 {
			return v
		}
	}
	return -1
}

func (g *Graph) dfsVisit(r, n int) {
	var S []int
	S = append([]int{r}, S...)
	g.color[r] = GRAY
	g.tt++
	g.d[r] = g.tt

	for len(S) != 0 {
		u := S[0]
		v := g.next(u, n)
		if v == -1 {
			S = S[1:]
			g.color[u] = BLACK
			g.tt++
			g.f[u] = g.tt
			continue
		}

		if g.color[v] != WHITE {
			continue
		}

		g.color[v] = GRAY
		g.tt++
		g.d[v] = g.tt
		S = append([]int{v}, S...)
	}
}

func (g *Graph) dfs(n int) string {
	for i := 0; i < n; i++ {
		g.color[i] = WHITE
	}
	g.tt = 0

	for u := 0; u < n; u++ {
		if g.color[u] == WHITE {
			g.dfsVisit(u, n)
		}
	}

	var out bytes.Buffer
	for i := 0; i < n; i++ {
		out.WriteString(fmt.Sprintf("%d %d %d\n", i+1, g.d[i], g.f[i]))
	}

	return strings.TrimRight(out.String(), "\n")
}

func answer(reader io.Reader) string {
	sc := bufio.NewScanner(reader)
	sc.Split(bufio.ScanWords)

	sc.Scan()
	n, _ := strconv.Atoi(sc.Text())

	var g Graph
	for i := 0; i < n; i++ {
		sc.Scan()
		u, _ := strconv.Atoi(sc.Text())
		sc.Scan()
		k, _ := strconv.Atoi(sc.Text())
		u--
		for j := 0; j < k; j++ {
			sc.Scan()
			v, _ := strconv.Atoi(sc.Text())
			v--
			g.M[u][v] = 1
		}
	}

	return g.dfs(n)
}

func main() {
	fmt.Println(answer(os.Stdin))
}

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

vector<vector<int>> v;
vector<int> d, f;

int t = 0;
void dfs(int x){
  d[x] = ++t;
  for(int i=0; i<v[x].size(); ++i){
    if(v[x][i] == 1 && d[i] == 0){
      dfs(i);
    }
  }
  f[x] = ++t;
}

int main(){
  int n; cin >> n;

  v.resize(n);
  d.resize(n);
  f.resize(n);

  for(int i=0; i<n; ++i) v[i].resize(n);

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

  for(int i=0; i<n; ++i){
    if(d[i] == 0) dfs(i);
  }

  for(int i=0; i<n; ++i){
      cout << i+1 << " " << d[i] << " " << f[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, 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>
using namespace std;

int n, t;
int A[101][101];
int d[101], f[101];

void depthFirstSearch(int r) {
	d[r] = ++t;
	for (int i = 1; i <= n; i++) {
		if (A[r][i] == 1 && d[i] == 0) depthFirstSearch(i);
	}
	f[r] = ++t;
	return;
}

int main() {
	int u, v, l;
	t = 0;
	cin >> n;

	for (int i = 1; i <= n; i++) {
		d[i] = f[i] = 0;
	}

	for (int i = 1; i <= n; i++) {
		for (int j = 1; j <= n; j++) {
			A[i][j] = 0;
		}
	}

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

	for (int i = 1; i <= n; i++) {
		if (d[i] == 0) depthFirstSearch(i);
	}

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

	return 0;
}

C++: #include <bits/stdc++.h>
#define FOR(i, a, b) for (int i = (a), i##_max = (b); i < i##_max; ++i)
#define RFOR(i, a, b) for (int i = (b)-1, i##_min = (a); i >= i##_min; --i)
#define REP(i, n) for (int i = 0, i##_len = (n); i < i##_len; ++i)
#define RREP(i, n) for (int i = (n)-1; i >= 0; --i)
#define ALL(obj) (obj).begin(), (obj).end()

using namespace std;
using vi = vector<int>;
using vd = vector<double>;
using i64 = int64_t;

constexpr int INF = 1 << 30;
constexpr int MOD = 1000000007;

template <typename T>
void print(vector<T> &v) {
  REP(i, v.size()) {
    if (i) cout << " ";
    cout << v[i];
  }
  cout << endl;
}

constexpr int N = 100;
enum Color { White, Gray, Black };
vector<vi> M(N, vi(N, 0));
vi d(N), f(N), nt(N, 0);
vector<Color> color(N, White);

int next(int u) {
  FOR(v, nt[u], nt.size()) {
    nt[u] = v + 1;
    if (M[u][v]) return v;
  }
  return -1;
}

void dfs_visit(int r, int &tt) {
  fill(nt.begin(), nt.end(), 0);
  stack<int> S;
  S.push(r);
  color[r] = Gray;
  d[r] = ++tt;

  while (!S.empty()) {
    auto u = S.top();
    auto 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(int n, int &tt) {
  REP(u, d.size()) {
    if (color[u] == White) dfs_visit(u, tt);
  }
  REP(i, d.size()) cout << i + 1 << " " << d[i] << " " << f[i] << endl;
}

int main() {
  int n, u, k, v;
  cin >> n;
  REP(i, n) {
    cin >> u >> k;
    REP(j, k) {
      cin >> v;
      M[u - 1][v - 1] = 1;
    }
  }
  int tt = 0;
  d.resize(n);
  f.resize(n);
  nt.resize(n);
  dfs(n, tt);
}

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

//#define int long long
//struct Fast {Fast(){cin.tie(0);ios::sync_with_stdio(0);}} fast;
//const int MOD = 1e9 + 7;
using intpair = pair<int, int>;

#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define reps(i, n, m) for (int i = (int)(n); i <= (int)(m); i++)
#define ALL(obj) (obj).begin(), (obj).end()
#define rALL(obj) (obj).rbegin(), (obj).rend()
#define ceiv(a, b) ((int)((a) + (b) - 1)/(int)(b))

vector<vector<int>> graph;
vector<int> d(100, -1), f(100,-1);
vector<bool> visited(100, false);

int dfs(int n, int t){
    d[n] = ++t;
    visited[n] = true;
    for(int to : graph[n]){
        if(visited[to]) continue;
        t = dfs(to, t);
    }
    f[n] = ++t;
    return t;
}

signed main(){
    int n; cin >> n;
    graph.resize(n);
    
    rep(i,n){
        int u, k;
        cin >> u >> k;
        graph[u-1] = vector<int>(k);
        rep(j,k){
            cin >> graph[u-1][j];
            graph[u-1][j]--;
        }
    }
    
    int t = 0;
    rep(i,n){
        if(!visited[i]) t = dfs(i,t);
    }
    rep(i,n){
        printf("%d %d %d\n", i+1, d[i], f[i]);
    }
}