Go: package main

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

var N int
var A [][]int
var t int
var color, d, f []int

const (
	WHITE = iota
	GRAY
	BLACK
)

func dfsVisit(u int) {
	color[u] = GRAY
	t ++
	d[u] = t
	for v:=0; v<N; v++ {
		if A[u][v] == 0 {
			continue
		}
		if color[v] == WHITE {
			dfsVisit(v)
		}
	}
	color[u] = BLACK
	t++
	f[u] = t
}

func dfs() {
	for u:=0; u<N; u++ {
		if color[u] == WHITE {
			dfsVisit(u)
		}
	}
	for u:=0; u<N; u++{
		fmt.Printf("%d %d %d\n", u+1, d[u], f[u])
	}
}


func nextInt(scanner *bufio.Scanner) int {
	scanner.Scan()
	num, _ := strconv.Atoi(scanner.Text())
	return num
}

func main() {
	scanner := bufio.NewScanner(os.Stdin)
	scanner.Split(bufio.ScanWords)
	N = nextInt(scanner)
	color = make([]int, N)
	d = make([]int, N)
	f = make([]int, N)
	A = make([][]int, N)
	for i:=0; i<N; i++{
		A[i] = make([]int, N)
	}
	for i:=0; i<N; i++{
		index := nextInt(scanner) - 1
		cnt := nextInt(scanner)
		for j:=0; j<cnt; j++ {
			v := nextInt(scanner) - 1
			A[index][v] = 1
		}
	}
	dfs()
}

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

int n,u,k,v;
int g[102][102];
int d[102],f[102];
int sn[102];
int cnt=1;

void dfs(int x);

int main(){
  memset(d,0,sizeof(d));
  cin>>n;
  for(int i=1;i<=n;i++){
    cin>>u>>k;
    sn[i]=0;
    for(int j=1;j<=k;j++){
      cin>>v;
      g[u][v]=1;
    }
  }
  
  dfs(1);

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

  return(0);
}

void dfs(int x){
  
  sn[x]=1;
  d[x]=cnt;
  cnt++;
  
  for(int i=1;i<=n;i++){
    if(g[x][i]==1 && sn[i]==0){
      dfs(i);
    }
  }

  f[x]=cnt;
  cnt++;

}

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

#define rep(i, n) for (int i=0; i<(n); ++i)
using ll = long long;
using P = pair<int, int>;

const int WHITE = 0;
const int GRAY = 1;
const int BLACK = 2;
const int MAX = 103;
int G[MAX][MAX];
int color[MAX];
int nt[MAX], d[MAX], f[MAX];
int tt, n;

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

void dfs_visit(int r) {
  memset(nt, 0, sizeof(nt));
  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() {
  memset(color, WHITE, sizeof(color));
  memset(nt, 0, sizeof(nt));
  tt = 0;

  rep(u,n) {
    if (color[u] == WHITE) dfs_visit(u);
  }
  rep(i,n) {
    cout << i+1 << ' ' << d[i] << ' ' << f[i] << endl;
  }
}

int main() {

  cin >> n;
  rep(i,n) memset(G[i], WHITE, sizeof(G[i])); // init
  int u, k;
  rep(i,n) {
    cin >> u >> k;
    rep(j,k) {
      int t;
      cin >> t;
      G[i][t-1] = 1;
    }
  }

  dfs();

  return 0;
}

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

vector<vector<int>> g;
vector<int> f,d;
vector<bool> seen;
int tim = 1;

void dfs(int now){
  seen[now] = true;
  d[now] = tim;
  tim++;
  
  for(int next: g[now]){
    if(seen[next]){
      continue;
    }
    dfs(next);
  }
  f[now] = tim;
  tim++;
}

int main(){
  int n;
  cin >> n;
  g = vector<vector<int>>(n);
  f = d = vector<int>(n);
  seen = vector<bool>(n,false);

  for (int i = 0; i < n; i++)
  {
    int u,k;
    cin >> u >> k;
    for (int j = 0; j < k; j++)
    {
      int v;
      cin >> v;
      g[i].push_back(v-1);
    }
  }

  for (int i = 0; i < n; i++)
  {
    if(!seen[i]) dfs(i);
  }
  for (int i = 0; i < n; i++)
  {
    cout << i+1 << " " << d[i] << " " << f[i] << endl;
  }  
}

C++: #include<bits/stdc++.h>
#define ll long long int
#define FOR(i,a,b) for(ll i=(ll)(a);i<(ll)(b);i++)
#define REP(i,n) FOR(i,0,n)
#define REP1(i,n) FOR(i,1,n)

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], color[N], d[N], f[N], tt;

void dfs_visit(int u) {
  color[u] = gray;
  d[u] = ++tt;
  REP(v, n) {
    if ( M[u][v] == 0) continue;
    if ( color[v] == white ) {
      dfs_visit(v);
    }
  }
  color[u] = black;
  f[u] = ++tt;
}

void dfs() {
  REP(u, n) color[u] = white;
  tt = 0;

  REP(u, n) {
    if ( color[u] == white ) dfs_visit(u);
  }
  REP(u, n) {
    cout << u + 1 << " " << d[u] << " " << f[u] << endl;
  }
}

int main() {
  int u, v, k;

  cin >> n;
  REP(i, n) {
    REP(j, n) {
      M[i][j] = 0;
    }
  }

  REP(i, n) {
    cin >> u >> k;
    u--;
    REP(j, k) {
      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 WHITE = 0;
static const int GRAY = 1;
static const int BLACK = 2;

int n, tt;
int M[N][N], color[N], d[N], f[N], nt[N]; 

int next(int u){
	for(int v = nt[u]; v < n; v++) {
		nt[u] = v + 1;
		if(M[u][v] = 1) 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 {
		   color[v] = BLACK;
		   S.pop();
		   f[v] = ++tt;
		}
	} 
}


void dfs() {
	for(int i = 0; i < n; i++) {
	     color[i] = WHITE;
	}	
	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 n, k , u, v;
	cin >> n;
	for(int i = 0; i < n; i++) {
		for(int j = 0; j < n; j++) {
			M[i][j] = 0;
		}
	}
	cin >> k >> u;
	u--;
	for(int i = 0; i < k; i++) {
	    cin >> v;
	    v--;
		M[u][v] = 1; 
	}
	dfs();
	return 0;
}

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

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;
};