Go: package main

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

type TimeRecord struct {
	discoverTime int
	finishTime   int
}

func main() {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)

	n, err := nextInt(sc)
	if err != nil {
		panic(err)
	}

	timeRecordMap := make([]TimeRecord, n)
	childrenMap := make([][]int, n)
	for i := 1; i <= n; i++ {
		node, err := nextInt(sc)
		if err != nil {
			panic(err)
		}
		timeRecordMap[node-1] = TimeRecord{-1, -1}

		childNum, err := nextInt(sc)
		if err != nil {
			panic(err)
		}
		childrenMap[node-1] = make([]int, childNum)
		for j := 0; j < childNum; j++ {
			child, err := nextInt(sc)
			if err != nil {
				panic(err)
			}
			childrenMap[node-1][j] = child
		}
	}

	timer := 1
	for {
		startNode := findStartNode(childrenMap, timeRecordMap)
		if startNode > 0 {
			visit(startNode, &timer, childrenMap, timeRecordMap)
		} else {
			break
		}
	}
	for k, v := range timeRecordMap {
		fmt.Printf("%d %d %d\n", k+1, v.discoverTime, v.finishTime)
	}
}

func findStartNode(childrenMap [][]int, timeRecordMap []TimeRecord) int {
	x := -1
	for node, timeRecord := range timeRecordMap {
		if timeRecord.discoverTime < 0 {
			x = node + 1
			break
		}
	}
	if x < 0 {
		return -1
	}

	found := false
	i := 0
	for i < len(childrenMap) {
		children := childrenMap[i]
		for j := 0; j < len(children); j++ {
			if children[j] == x {
				x = j + 1
				found = true
				break
			}
		}
		if found {
			i = 0
		} else {
			i++
		}
	}
	return x
}

func visit(currentNode int, timer *int, childrenMap [][]int, timeRecordMap []TimeRecord) {
	if timeRecordMap[currentNode-1].discoverTime > 0 {
		return
	}
	children := childrenMap[currentNode-1]
	timeRecordMap[currentNode-1] = TimeRecord{*timer, timeRecordMap[currentNode-1].finishTime}
	(*timer)++
	for i := 0; i < len(children); i++ {
		visit(children[i], timer, childrenMap, timeRecordMap)
	}
	timeRecordMap[currentNode-1] = TimeRecord{timeRecordMap[currentNode-1].discoverTime, *timer}
	(*timer)++
}

func nextInt(sc *bufio.Scanner) (int, error) {
	sc.Scan()
	return strconv.Atoi(sc.Text())
}

C++: #include <bits/stdc++.h>
using namespace std;
#define rep(i,n) for(int i=0;i<n;i++)
using ll = long long;
#define White 0
#define Black 1
static const int MAX=100;

int C[MAX],d[MAX],f[MAX];
vector<int> adj[MAX];
void init(){
    rep(i,MAX)C[i]=White;
}
int tt=0;
void solve(int node){
    d[node]=++tt;
    C[node]=Black;
    for(int x:adj[node]){
        if(C[x]==White)solve(x);
    }
    f[node]=++tt;
    return;
}

int main(){
    int n;cin>>n;
    init();
    rep(i,n){
        int id,k,node;
        scanf("%d %d",&id,&k);
        id--;
        rep(j,k){
            scanf("%d",&node);
            node--;
            adj[id].push_back(node);
        }
    }
    rep(i,n){
        if(C[i]==White)solve(i);
    }
    rep(i,n){
        printf("%d %d %d\n",i+1,d[i],f[i]);
    }
    return 0;
}

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

using namespace std;

static const int N = 100; // 1 <= n <= 100
static const int WHITE = 0; // 未訪問は0
static const int GRAY = 1; // 訪問中は1
static const int BLACK = 2; // 訪問完了は2

int n; // 頂点数n
vector<vector<int>> M(N, vector<int>(N,0)); // M[u][v]：uからvに出ているか否か
vector<int> color(N), d(N), f(N); // d(i)：頂点i発見時刻，f(i)：頂点i完了時刻
int tt; // 経過時間tt
vector<int> nt(N); //

// uに隣接するvを番号順に取得
int next(int u) {
    for ( int v = nt[u]; v < n; v++ ) {
        nt[u] = v + 1;
        if (M[u][v]) {
            return v;
        }
    }
    return -1;
}

// 地点rについてスタックを用いた深さ優先探索
void dfs_visit(int r) {
    //初期化
    for ( int i = 0; i < n; i++ ){
        nt[i] = 0;
    }
    stack<int> S;
    S.push(r);
    color[r] = GRAY;
    
    tt++;
    d[r] = tt;
    
    while ( !S.empty() ) {
        int u = S.top();
        int v = next(u);
        if ( v != -1 ) {
            if ( color[v] == WHITE ) {
                color[v] = GRAY;
                tt++;
                d[v] = tt;
                S.push(v);
            }
        }else{
            S.pop();
            color[u] = BLACK;
            tt++;
            f[u] = tt;
        }
    }
}

void dfs() {
    // 初期化
    for ( int i = 0; i < n; i++ ) {
        color[i] = WHITE;
        nt[i] = 0;
    }
    tt = 0;
    
    // 未訪問のuを始点として深さ優先探索
    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++){
        cin >> u >> k;
        u--;
        for(int j=0;j<k;j++){
            cin >> v;
            v--;
            M[u][v] = 1;
        }
    }
        
        dfs();
        return 0;
}

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

using namespace std;

static const int N = 100;
static const int UNVISITED = 0;
static const int VISITING = 1;
static const int VISITED = 2;


int n;
int A[N][N];
int d[N];
int f[N];
int states[N];
int nt[N];
int t;

int next(int u){
  for(int v = nt[u];v < n;v++){
    nt[u] = v + 1;
    //cout << nt[u] << '\n';
    if(A[u][v]) return v;
  }
  return -1;
}

void dfs_visit(int x){
  for(int i = 0;i < n;i++){
    nt[i] = 0;
  }
  
  stack<int> s;
  s.push(x);
  states[x] = VISITING;
  d[x] = ++t;
  
  while(!s.empty()){
    int u = s.top();
    int v = next(u);
    //cout << "u:" << u << " v:" << v << '\n';
    if(v != -1){
      if(states[v] == UNVISITED){
	states[v] = VISITING;
	d[v] = ++t;
	s.push(v);
      }
    }else{
      s.pop();
      states[u] = VISITED;
      f[u] = ++t;
    }
  }
}

void dfs(){
  for(int i = 0;i < n;i++){
    states[i] = UNVISITED;
  }

  t = 0;

  for(int u = 0;u < n;u++){
    if(states[u] == UNVISITED) dfs_visit(u);
  }
  for(int i = 0;i < n;i++){
    cout << i + 1 << " " << d[i] << " " << f[i] << '\n';
  }
}
         
int main(){ 
  cin >> n;
  
  for(int i = 0;i < n;i++){
    for(int j = 0;j < n;j++){
      A[i][j] = 0;
    }
  }
  
  int k,u,v;
  
  for(int i = 0;i < n;i++){
    cin >> u >> k;
    u--;
    for(int j = 0;j < k;j++){
      cin >> v;
      v--;
      A[u][v] = 1;
    }
  }

  dfs();

  return 0;
}

C++: #include "bits/stdc++.h"
#include <unordered_set>

#define _CRT_SECURE_NO_WARNINGS

#define REP(i, n) for(decltype(n) i = 0; i < (n); i++)
#define REP2(i, x, n) for(decltype(x) i = (x); i < (n); i++)
#define REP3(i, x, n) for(decltype(x) i = (x); i <= (n); i++)
#define RREP(i, n) for (decltype(n) i = (n) - 1; i >= 0; i--)

#define ALL(a) (a).begin(),(a).end()
#define SORT(c) sort((c).begin(),(c).end())
#define DESCSORT(c) sort(c.begin(), c.end(), greater<int>())

using namespace std;

const int INF = 1000000000;
const double PI = 3.1415926535897932384626433832795;

// N, E, S, W
const int dx[4] = { -1, 0,  1,  0 };
const int dy[4] = { 0, 1,  0, -1 };

using LL = long long int;
using LD = long double;
using pii = pair<int, int>;
using pdd = pair<double, double>;
using pll = pair<LL, LL>;
using vi = vector<int>;
using vd = vector<double>;
using vs = vector<string>;
using vvi = vector<vi>;
using vll = vector<LL>;

//==============================================
int n, tm = 0;
vvi M;
vi D, F, searchStatus;

void dfs(int u) {
	searchStatus[u] = 0;
	D[u] = ++tm;
	REP3(i, 1, n) {
		if (M[u][i] == 0) continue;

		if (searchStatus[i] == -1) {
			dfs(i);
		}
	}
	F[u] = ++tm;
	searchStatus[u] = 1;
}

void print() {
	REP3(i, 1, n) {
		cout << i << " " << D[i] << " " << F[i] << "\n";
	}
}

void solve() {
	REP3(i, 1, n) searchStatus[i] = -1;

	REP3(i, 1, n) {
		if (searchStatus[i] == -1) {
			dfs(i);
		}
	}

	print();
}

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

	cin >> n;
	
	M.resize(n + 1, vi(n + 1));
	D.resize(n + 1);
	F.resize(n + 1);
	searchStatus.resize(n + 1);

	int u, k, v;
	REP3(i, 1, n) {
		cin >> u >> k;
		REP3(j, 1, k) {
			cin >> v;
			M[u][v] = 1;
		}
	}

	solve();
	return 0;
}