Go: package main

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

/***************************************************************
stackによる深さ優先探索を実装する。
***************************************************************/

const (
	N     = 100
	WHITE = 0
	GRAY  = 1
	BLACK = 2
)

var (
	n            int
	Adj          [N][N]int
	statusColor  [N]int
	discoverTime [N]int
	finishTime   [N]int
	clock        int
	nt           [N]int
)

/***************************************************************
Stackの定義:
- field
	container: ノードの格納されたスライス
	sp: スタックポインタ
- method
	size(): スタックに積まれているノードの個数を返す
	top(): スタックの一番上に積まれているノードを返す
	isEmpty(): スタックが空かどうかを返す
	pop(): スタックの要素をポップし削除する
	push(): スタックに要素を積む
***************************************************************/

type Stack struct {
	container []int
	sp        int
}

func (s *Stack) size() int {
	return len(s.container)
}

func (s *Stack) top() int {
	return s.container[s.sp]
}

func (s *Stack) isEmpty() bool {
	return s.sp == 0
}

func (s *Stack) pop() int {
	_pop := func() {
		s.container = s.container[:len(s.container)-1]
	}
	defer _pop()
	if s.isEmpty() {
		panic("There is no elements in stack!")
	}
	s.sp--
	return s.container[s.sp]
}

func (s *Stack) push(n int) {
	s.sp++
	s.container[s.sp] = n
}

func next(u int) int {
	for v := nt[u]; v < n; v++ {
		nt[u] = v + 1
		if Adj[u][v] == 1 {
			return v
		}
	}
	return -1
}

func _DFS(target int) {
	for i := 0; i < n; i++ {
		nt[i] = 0
	}
	stack := new(Stack)
	stack.container = make([]int, N)
	stack.push(target)
	statusColor[target] = GRAY
	clock++
	discoverTime[target] = clock
	for !stack.isEmpty() {
		u := stack.top()
		v := next(u)
		if v != -1 {
			if statusColor[v] == WHITE {
				statusColor[v] = GRAY
				clock++
				discoverTime[v] = clock
				stack.push(v)
			}
		} else {
			stack.pop()
			statusColor[u] = BLACK
			clock++
			finishTime[u] = clock
		}
	}
}

func DFS() {
	for i := 0; i < n; i++ {
		statusColor[i] = WHITE
		nt[i] = 0
	}
	clock = 0
	for i := 0; i < n; i++ {
		if statusColor[i] == WHITE {
			_DFS(i)
		}
	}
	for i := 0; i < n; i++ {
		fmt.Printf("%d %d %d\n", i+1, discoverTime[i], finishTime[i])
	}
}

func main() {
	scanner := bufio.NewScanner(os.Stdin)
	scanner.Split(bufio.ScanWords)
	scanner.Scan()
	n, _ = strconv.Atoi(scanner.Text())
	for i := 0; i < n; i++ {
		for j := 0; j < n; j++ {
			Adj[i][j] = 0
		}
	}
	for i := 0; i < n; i++ {
		scanner.Scan()
		u, _ := strconv.Atoi(scanner.Text())
		scanner.Scan()
		k, _ := strconv.Atoi(scanner.Text())
		u--
		for j := 0; j < k; j++ {
			scanner.Scan()
			v, _ := strconv.Atoi(scanner.Text())
			v--
			Adj[u][v] = 1
		}
	}

	DFS()
}

C++: /**
 * code generated by JHelper
 * More info: https://github.com/AlexeyDmitriev/JHelper
 * @author champon
 */

#include <iostream>
#include <fstream>
#include<bits/stdc++.h>
#define se cout << "test ok" << endl;
#define sp << " " <<
#define enl "\n"
using namespace std;
using ll=long long;
using ld=long double;
ll mod = ll(1e9)+7;
ll inf = ll(1e18);
void bl(bool b, ostream& out=cout){ out << (b ? "Yes" : "No") << endl; }
void bl2(bool b, ostream& out=cout){ out << (b ? "YES" : "NO") << endl; }
template<typename T> inline bool chmax(T &a, T b){ if(a<b){a=b; return true;} return false; }
template<typename T> inline bool chmin(T &a, T b){ if(a>b){a=b; return true;} return false; }
int dx[] = {1, 0, -1, 0, 1, -1, 1, -1};
int dy[] = {0, 1, 0, -1, 1, -1, -1, 1};

#ifndef INCLUDE_DEBUG_HPP
#define INCLUDE_DEBUG_HPP

#include <iostream>
#include <vector>
#include <map>
using namespace std;

namespace dbg {
    using ll = long long;

    class Debug {
    public:
        Debug(){}
        template<typename T>
        void vd(vector<T> vec);
        template<typename T>
        void vd2(vector<vector<T>> vec);
        template<typename T>
        void ad(T *arr, ll n);
        template<typename T, size_t N>
        void ad2(T (&arr)[N], ll n);
        template<typename T>
        void md(T mp);
    };

    template<typename T>
    void Debug::vd(vector<T> vec) {
        for (auto vv : vec) cout << vv << " ";
        cout << endl;
    }

    template<typename T>
    void Debug::vd2(vector<vector<T>> vec) {
        for (auto vv : vec) {
            for (auto vvv : vv) cout << vvv << " ";
            cout << endl;
        }
    }

    template<typename T>
    void Debug::ad(T *arr, ll n) {
        for (int i = 0; i <= n; i++) cout << arr[i] << " ";
        cout << endl;
    }

    template<typename T, size_t N>
    void Debug::ad2(T (&arr)[N], ll n) {
        for (int i = 0; i <= N; i++) for (int j = 0; j <= n; j++) cout << arr[i][j] << " ";
        cout << endl;
    }

    template<typename T>
    void Debug::md(T mp) {
        cout << "key : value" << endl;
        for (auto const &m : mp) cout << m.first << " : " << m.second << endl;
        cout << endl;
    }

}

#endif //INCLUDE_DEBUG_HPP

using dbg::Debug;
Debug debug;

class dfs {
public:
    vector<set<int>> g;
    vector<int> d, f;

    int rec(int u, int cnt){
        d[u] = cnt;

        for(auto& to : g[u]){
            if(d[to]) continue;
            cnt = rec(to, cnt+1);
        }

        f[u] = ++cnt;
        return cnt;
    }

	void solve(std::istream& in, std::ostream& out) {
	    int n;
	    in >> n;
	    int u, k;
	    g.assign(n, set<int>());
	    for(int i=0; i<n; i++){
            in >> u >> k;
            int v;
            --u;
            for(int j=0; j<k; j++){
                in >> v;
                --v;
                g[u].insert(v);
            }
	    }

        d.assign(n, 0);
        f.assign(n, 0);

        bool flg = false;
        int start = 0;
        int cnt = 0;
        while(!flg) {
            cnt = rec(start, cnt+1);
            start = -1;
            for(int i=0; i<n; i++){
                if(!d[i]){
                    start = i;
                    break;
                }
            }
            if(start == -1) flg = true;
        }

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


int main() {
    cin.tie(nullptr);
    ios_base::sync_with_stdio(false);
	dfs solver;
	std::istream& in(std::cin);
	std::ostream& out(std::cout);
	solver.solve(in, out);
	return 0;
}

C++: #include <iostream>
using namespace std;
 
int visit[100],end[100],a[100][100];
int t,N,u,k,p;
 
void list(int N){
    for(int i=0;i<N;i++){
        cin>>u>>k;
        for (int j=0;j<k;j++){
            cin>>p;
            a[u-1][p-1]=1;
        }
    }
}
 
void sor(int cur,int N){
    t+=1;
    visit[cur]=t;
    for(int kyo=0;kyo<N;++kyo){
        if(a[cur][kyo]==1&&visit[kyo]==0){
            sor(kyo,N);
        }
    }
    t+=1;
    end[cur]=t;
}
 
int main(){
    cin >> N;
    list(N);
    for(int i=0;i<N;i++){
        if(visit[i] == 0) sor(i,N);
    }
    for(int i=0;i<N;i++){
        cout<<i+1<<' '<<visit[i]<<' '<<end[i]<<endl;
    }
}