Go: package main

/*
深さ優先探索
*/

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

func main() {
	scanner := makeScanner(8192)
	n := eGetInt(scanner)
	g := make([][]int, n+1)
	for i := 1; i < n+1; i++ {
		ints := eGetInts(scanner)
		num, vcount := ints[0], ints[1]
		g[i] = make([]int, vcount)
		for j := 0; j < vcount; j++ {
			g[num][j] = ints[j+2]
		}
	}
	hist := make([]struct{ d, f int }, n+1)
	t := 0
	var visit func(int)
	visit = func(num int) {
		if hist[num].d == 0 {
			stack := []int{}
			t++
			hist[num].d = t
			stack = append(stack, num)
			for len(stack) > 0 {
				// トップを訪問する
				top := stack[len(stack)-1]
				for i := 0; i < len(g[top]); i++ {
					if hist[g[top][i]].d == 0 {
						t++
						hist[g[top][i]].d = t
						stack = append(stack, g[top][i])
						goto endloop
					}
				}
				// 訪問場所がなくなったら
				// pop
				stack = stack[0 : len(stack)-1]
				t++
				hist[top].f = t
			endloop:
			}
		}
	}
	for i := 1; i < n+1; i++ {
		visit(i)
	}
	for i := 1; i < n+1; i++ {
		fmt.Println(i, hist[i].d, hist[i].f)
	}
}

////////////////////////////////////////////////////////////////////////////////
// ライブラリ
////////////////////////////////////////////////////////////////////////////////
func makeScanner(maxByte int) *bufio.Scanner {
	scanner := bufio.NewScanner(os.Stdin)
	scanner.Buffer(make([]uint8, 0, 8192), maxByte)
	return scanner
}
func makeWordScanner() *bufio.Scanner {
	scanner := makeScanner(8192)
	scanner.Split(bufio.ScanWords)
	return scanner
}
func eGetLine(r *bufio.Scanner) string {
	if r.Scan() {
		return r.Text()
	}
	err := r.Err()
	if err != nil {
		log.Fatal(err)
	}
	// EOF
	return ""
}
func eGetInt(r *bufio.Scanner) int {
	line := eGetLine(r)
	return eAtoi(line)
}
func eGetInt64(r *bufio.Scanner) int64 {
	line := eGetLine(r)
	return eAtoInt64(line)
}
func eGetFields(r *bufio.Scanner) []string {
	line := eGetLine(r)
	return strings.Fields(line)
}
func eGetInts(r *bufio.Scanner) []int {
	fields := eGetFields(r)
	ints := make([]int, len(fields))
	for i := 0; i < len(ints); i++ {
		ints[i] = eAtoi(fields[i])
	}
	return ints
}
func eGetInt64s(r *bufio.Scanner) []int64 {
	fields := eGetFields(r)
	ints := make([]int64, len(fields))
	for i := 0; i < len(ints); i++ {
		ints[i] = eAtoInt64(fields[i])
	}
	return ints
}
func eGetChars(r *bufio.Scanner) []string {
	line := eGetLine(r)
	return strings.Split(line, "")
}
func eAtoi(s string) int {
	n, err := strconv.Atoi(s)
	if err != nil {
		log.Fatal(err)
	}
	return n
}
func eAtoInt64(s string) int64 {
	n, err := strconv.ParseInt(s, 10, 64)
	if err != nil {
		log.Fatal(err)
	}
	return n
}

C++: #include <iostream>
#include <algorithm>
#include <string>
#include <vector>
#include <cstdio>
#include <cmath>
#include <cstdlib>
#include <cstring>
#include <stack>
#include <queue>
#include <set>
#include <map>
#include <list>
#include <utility>
#include <ctime>
#define INF 1000000000
#define LINF 9000000000000000000
#define mod 1000000007
 
#define rep(i,n) for(int i=0;i<int(n);i++)
#define rrep(i,n) for(int i=(n);i>=0;i--)
#define REP(i,a,b) for(int i=(a);i<int(b);i++)
#define all(x) (x).begin(),x.end()
#define vector_rsort(x) sort(all(x));reverse(all(x))
#define array_rsort(x,n) sort(x,x+n);reverse(x,x+n);
#define pb push_back
#define mp make_pair
#define MOD(x) (x%(mod))

#define Yes cout<<"Yes"<<endl
#define YES cout<<"YES"<<endl
#define No cout<<"No"<<endl
#define NO cout<<"NO"<<endl
using namespace std;
 
typedef long long ll;
typedef unsigned long long ull;
typedef vector<int> vi;
typedef pair<int,int> pi;
 
int dx[4]={1,0,-1,0};
int dy[4]={0,1,0,-1};
bool debug=false;
/*---------------------------------------------------*/

int n,t=0;
int d[105],f[105];
int used[105];
vi g[105];

void init(){
  rep(i,105){
    d[i]=f[i]=INF;
  }
}

void dfs(int now){
  t++;
  d[now]=t;
  used[now]=true;
  rep(i,g[now].size()){
    if(!used[g[now][i]]){
      dfs(g[now][i]);
    }
  }
  t++;
  f[now]=t;
}

int main(){
  int u,k,v;
  cin>>n;
  rep(i,n){
    cin>>u>>k;
    rep(j,k){
      cin>>v;
      g[u].pb(v);
    }
  }
  init();
  REP(i,1,n+1)if(!used[i])dfs(i);
  REP(i,1,n+1){
    cout<<i<<" "<<d[i]<<" "<<f[i]<<endl;
  }
  return 0;
}

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

struct graph {
	struct node {vector<int> v; int d = 0, f;};
	map<int, node> nodes;
	int count = 1;

	void read_all() {
		int n, id, k, v;
		cin >> n;
		while (n--) {
			cin >> id >> k;
			while (k--) {
				cin >> v;
				nodes[id].v.push_back(v);
			}
		}
	}
	void traverse(int id) {
		if (nodes[id].d)
			return;
		nodes[id].d = count++;
		for (int x: nodes[id].v)
			traverse(x);
		nodes[id].f = count++;
	}
	void traverse() {
		for (auto n: nodes)
			traverse(n.first);
	}
	void display_all() {
		for (auto n: nodes)
			cout << n.first << " " << n.second.d << " " << n.second.f << endl;

	}
};

int main() {
	graph g;
	g.read_all();
	g.traverse();
	g.display_all();
}

C++: #include <cassert>
#include <algorithm>
#include <iostream>
#include <vector>
#include <string>

class TVertex
{
    int FIndex;
    std::vector<TVertex*> FList;
    int FDiscoveryTime;
    int FFinishTime;

public:
    TVertex(int Index)
     : FIndex(Index), FDiscoveryTime(0), FFinishTime(0)
    {}
    void AddPath(TVertex* Vertex)
    {
        FList.push_back(Vertex);
    }
    void PrintTime(std::ostream& out)const
    {
        out << FIndex << " " << FDiscoveryTime << " " << FFinishTime << std::endl;
    }
    int DepthFirstSearch(int Time)
    {
        if(FFinishTime) return Time;
        FDiscoveryTime = Time++;
        for(std::vector<TVertex*>::iterator It = FList.begin(); It != FList.end(); ++It){
            TVertex* V = *It;
            Time = V->DepthFirstSearch(Time);
        }
        FFinishTime = Time++;
        return Time;
    }
};
class TGraph
{
    std::vector<TVertex*> FTable;
    void Init(int n)
    {
        assert(n > 0);
        FTable.resize(n);
        for(int i = 0; i < n; ++i){
            FTable[i] = new TVertex(i);
        }
    }
public:
    TGraph(int n)
    {
        Init(n+1);
    }
    
    void SetupVertex(std::istream& in)
    {
        int Index;
        in >> Index;
        assert(Index >= 1);
        assert(Index <= FTable.size());
        int k;
        in >> k;
        for(int i = 0; i < k; ++i){
            int v;
            in >> v;
            FTable[Index]->AddPath(FTable[v]);
        }
    }
    void DepthFirstSearch()
    {
        FTable[1]->DepthFirstSearch(1);
    }
    void PrintTime(std::ostream& out)
    {
        for(int i = 1; i < FTable.size(); ++i){
            FTable[i]->PrintTime(out);
        }
    }
};

int main()
{
    int n;
    std::cin >> n;
    TGraph Graph(n);
    for(int i = 0; i < n; ++i){
        Graph.SetupVertex(std::cin);
    }
    Graph.DepthFirstSearch();
    Graph.PrintTime(std::cout);
    return 0;
    
}