Go: package main

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

type vertexId int

type vertex struct {
	id vertexId
	firstVisitAt int
	finishVisitAt int
	adjs []vertexId
}

func createVertex(id int, adjsInt []int) vertex {
	adjs := make([]vertexId, len(adjsInt))
	for i := 0; i < len(adjs); i++ {
		adjs[i] = vertexId(adjsInt[i])
	}
	return vertex{
		id: vertexId(id),
		firstVisitAt: 0,
		finishVisitAt: 0,
		adjs: adjs,
	}
}

func (v *vertex) doesAllAdjsVisited(vertices []vertex) bool {
	for _, vId := range v.adjs {
		adj := vertices[vId-1]
		if !adj.isVisited() {
			return false
		}
	}
	return true
}

func (v *vertex) isFirstVisit() bool {
	return v.firstVisitAt == 0
}

func (v *vertex) isVisited() bool {
	return v.firstVisitAt > 0
}

func (v *vertex) nextVertex(vertices []vertex) (vertexId, error) {
	for _, vId := range v.adjs {
		adj := vertices[vId-1]
		if !adj.isVisited() {
			return vId, nil
		}
	}
	return vertexId(-1), fmt.Errorf("illegal")
}

func dfs(currentId vertexId, timestamp int, vertices []vertex) int {
	timestamp = timestamp + 1
	currentVertex := &vertices[currentId-1]
	if currentVertex.isFirstVisit() {
		currentVertex.firstVisitAt = timestamp
	}
	for !currentVertex.doesAllAdjsVisited(vertices) {
		nextVertexId, _ := currentVertex.nextVertex(vertices)
		timestamp = dfs(nextVertexId, timestamp, vertices)
	}
	timestamp = timestamp + 1
	currentVertex.finishVisitAt = timestamp
	return timestamp
}

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

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

	vertices := make([]vertex, n)
	for i := 0; i < n; i++ {
		id, err := nextInt(sc)
		if err != nil {
			panic(err)
		}
		adjN, err := nextInt(sc)
		if err != nil {
			panic(err)
		}
		adjs := make([]int, adjN)
		for j := 0; j < adjN; j++ {
			adjId, err := nextInt(sc)
			if err != nil {
				panic(err)
			}
			adjs[j] = adjId
		}
		vertices[i] = createVertex(id, adjs)
	}

	dfs(vertexId(1), 0, vertices)

	for i := 0; i < n; i++ {
		fmt.Printf("%d %d %d\n", vertices[i].id, vertices[i].firstVisitAt, vertices[i].finishVisitAt)
	}
}

func nextText(sc *bufio.Scanner) string {
	sc.Scan()
	return sc.Text()
}

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

C++: #include<algorithm>
#include<iostream>
#include<cstdlib>
#include<cstring>
#include<cstdio>
#include<vector>
#include<queue>
#include<stack>
#include<cmath>
#include<list>
#include<map>
#include<set>
using namespace std;

typedef vector<int> VI;
typedef vector<VI> VVI;
typedef vector<string> VS;
typedef stack<int> SI;
typedef pair<int,int> PII;
typedef long long LL;

#define d(x)  cout<<#x<<" = "<<(x)<<endl;
#define ALL(a)  (a).begin(),(a).end()
#define RALL(a) (a).rbegin(), (a).rend()
#define PB push_back
#define MP make_pair
#define SZ(a) int((a).size())
#define EACH(i,c) for(typeof((c).begin()) i=(c).begin(); i!=(c).end(); ++i)
#define REACH(i,c) for(typeof((c).rbegin()) i=(c).rbegin(); i!=(c).rend(); ++i)
#define EXIST(s,e) ((s).find(e)!=(s).end())
#define SORT(c,n) sort(c,c+n)
#define VSORT(c) sort((c).begin(),(c).end())
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP(i,n)  FOR(i,0,n)
#define DFOR(i,b,a) for(int i=(b)-1;i>=(a);--i)
#define DREP(i,n) DFOR(i,n,0)
#define INF 2000000000

const double EPS = 1e-10;
const double PI  = acos(-1.0);
////////////////////////////////////////////////
//?????????????????????????????????
SI s;//?¨?????????????????????????
int n;//??????????????°
int t;//??????
int d[101];//??????????????????????¨????????????????????????????????????????
int f[101];//??????????????£??\?????????????????????????????????????????????????????????
int a[101][101];//??£??\?????????
int p[101];//??£??\?????????????¨???????????????????????????????
int flag;//???
int main()
{
	cin>>n;
	FOR(i,1,n+1)//??£??\??????????????????
	{
		int k,m;cin>>k>>m;
		a[k][0]=m;
		FOR(j,1,m+1)
		{
			int x;cin>>x;
			a[k][j]=x;
		}
	}
	d[1]=1;
	FOR(i,1,101)p[i]=1;//??£??\??????????????????????????????????????????1???????????????
	for(s.push(1),t=2;;t++)
	{
		//s.top()?????????????????????????????????
		if(a[s.top()][0]==0)
		{
			f[s.top()]=t;
			s.pop();
		}
		else
		{
			int next=a[s.top()][p[s.top()]];//next????¬?????¨?????????????????????????
			for(;d[next]!=0;)//???????????????????¨??????????????????¢???
			{
				p[s.top()]++;//????????????????????????????¬??????????????????????
				if(p[s.top()]>a[s.top()][0])//?????????????????£????????????????????????????¨??????????????????°
				{
					f[s.top()]=t;
					s.pop();//?¬?????¨????????????????????????????
					flag=1;//???????????????
					break;//????????????????????????
				}
				next=a[s.top()][p[s.top()]];//?¨????????????????????????´??°
			}
			if(flag==0)//?????????????????£???????????????????¨??????????????????°
			{
				s.push(next);//?¬?????¨??????????for???????????§??????????????????
				d[s.top()]=t;//???????????????????????????????????????????¨????????????????????????????????????????
			}
		}
		flag=0;//???????????????
		if(f[1]!=0)break;//??¢?´¢??????
	}
	FOR(i,1,n+1)cout<<i<<" "<<d[i]<<" "<<f[i]<<endl;
	return 0;
}

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;
//?????\??????
int M[N][N];
//???°??????¶????????¢????
int color[N];
//??\???¶?????????°???¶???
int d[N];
//??\???¶????????????¶???
int f[N];
//???¶???
int tt;
 
int nt[N];
 
//????????????????????????u?????????v
int next(int u){
    for(int v=nt[u];v<n;v++){
        nt[u]=v+1;
        if(M[u][v]&&color[v]==WHITE)
            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&&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;
    tt=0;
 
    //??\????????????u??????????????????±??????????????´?¢
    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();
}

C++: #include <cstdio>

typedef struct Node {
    int id;
    int d;
    int f;
    int count;
} Node;


int count(int id, int now, Node *node, int a[101][100]){
    if(node[id].d == 0) node[id].d = now;
    if(node[id].f != 0) return now - 1;
    for(int i = 0; i < node[id].count; ++i){
        int nextId = a[id][i];
        if(nextId == id) continue;
        now = count(nextId, now + 1, node, a);
    }
    node[id].f = now + 1;
    return node[id].f;
}

int main(){
    int n;
    std::scanf("%d", &n);
    Node node[101];
    int a[101][100];
    for(int i = 1; i <= n; ++i){
        int id;
        std::scanf("%d", &id);
        node[id].id = id;
        std::scanf("%d", &node[id].count);
        for(int j = 0; j < node[id].count; ++j){
            std::scanf("%d", &a[id][j]);
        }
    }
    int now = 0;
    for(int i = 1; i <= n; ++i){
        now = count(i, now + 1, node, a);
    }
    for(int i = 1; i <= n; ++i){
        std::printf("%d %d %d\n", node[i].id, node[i].d, node[i].f);
    }

    return 0;
}