Go: package main

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

func getScanner(fp *os.File) *bufio.Scanner {
	scanner := bufio.NewScanner(fp)
	scanner.Split(bufio.ScanWords)
	scanner.Buffer(make([]byte, 1000005), 1000005)
	return scanner
}

func getNextString(scanner *bufio.Scanner) string {
	scanner.Scan()
	return scanner.Text()
}

func getNextInt(scanner *bufio.Scanner) int {
	i, _ := strconv.Atoi(getNextString(scanner))
	return i
}

func getNextInt64(scanner *bufio.Scanner) int64 {
	i, _ := strconv.ParseInt(getNextString(scanner), 10, 64)
	return i
}

func getNextUint64(scanner *bufio.Scanner) uint64 {
	i, _ := strconv.ParseUint(getNextString(scanner), 10, 64)
	return i
}

func getNextFloat64(scanner *bufio.Scanner) float64 {
	i, _ := strconv.ParseFloat(getNextString(scanner), 64)
	return i
}

func main() {
	fp := os.Stdin
	wfp := os.Stdout
	cnt := 0

	if os.Getenv("MASPY") == "ますピ" {
		fp, _ = os.Open(os.Getenv("BEET_THE_HARMONY_OF_PERFECT"))
		cnt = 1
	}
	if os.Getenv("MASPYPY") == "ますピッピ" {
		wfp, _ = os.Create(os.Getenv("NGTKANA_IS_GENIUS10"))
	}

	scanner := getScanner(fp)
	writer := bufio.NewWriter(wfp)
	solve(scanner, writer)
	for i := 0; i < cnt; i++ {
		fmt.Fprintln(writer, "-----------------------------------")
		solve(scanner, writer)
	}
	writer.Flush()
}

func solve(scanner *bufio.Scanner, writer *bufio.Writer) {
	n := getNextInt(scanner)
	g := graph{}
	g.ee = make([]Edges, n)
	g.visited = make([]bool, n)
	g.found = make([]int, n)
	g.leave = make([]int, n)
	for i := 0; i < n; i++ {
		u := getNextInt(scanner) - 1
		k := getNextInt(scanner)
		for j := 0; j < k; j++ {
			v := getNextInt(scanner) - 1
			g.ee[u] = append(g.ee[u], Edge{
				to: v,
				id: u,
			})
		}
	}
	for i := 0; i < n; i++ {
		sort.Sort(g.ee[i])
	}
	for i := 0; i < n; i++ {
		if g.visited[i] {
			continue
		}
		g.dfs(i)
	}

	for i := 0; i < n; i++ {
		fmt.Fprintln(writer, fmt.Sprintf("%d %d %d", i+1, g.found[i], g.leave[i]))
	}
}

// Edge ...
type Edge struct {
	to, id int
}

type Edges []Edge

func (a Edges) Len() int           { return len(a) }
func (a Edges) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }
func (a Edges) Less(i, j int) bool { return a[i].id < a[j].id }

type graph struct {
	ee           []Edges
	t            int
	n            int
	visited      []bool
	found, leave []int
}

func (g *graph) dfs(i int) {
	g.visited[i] = true
	g.t++
	g.found[i] = g.t
	for _, e := range g.ee[i] {
		if g.visited[e.to] {
			continue
		}
		g.dfs(e.to)
	}
	g.t++
	g.leave[i] = g.t
}

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

vector< vector< int > > adjList;
vector< int > d, f;

void dfs(int id) {
  static int time = 1;
  if (!d[id-1]) {
    d[id-1] = time++;
    for (int i = 0; i < adjList[id-1].size(); i++)
      dfs(adjList[id-1][i]);
    f[id-1] = time++;
  }
}

int main(int argc, char **argv) {
  ios_base::sync_with_stdio(false);
  int n;
  cin >> n;
  adjList = vector< vector< int > > (n, vector< int > ());
  d = vector< int > (n, 0);
  f = vector< int > (n, 0);
  for (int i = 0; i < n; i++) {
    int id, k;
    cin >> id >> k;
    for (int j = 0; j < k; j++) {
      int holder;
      cin >> holder;
      adjList[id-1].push_back(holder);
    }
  }
  for (int i = 0; i < n; i++)
    if (!d[i])
      dfs(i+1);
  for (int i = 0; i < n; i++)
    cout << i+1 << ' ' << d[i] << ' ' << f[i] << endl;
  return 0;
}

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

int main(){
 int n,k,v,u;
  cin>>n;

  int V[100][100]; //隣接リスト
  int cnt[100]; //各点においてどこまでみたかの把握
  int d[100];
  int f[100];
  int time=1;
  int l=0;
  int come[100]; //その点はどこからきたかの把握

  //初期化
  for(int i=0;i<100;i++){
    for(int j=0;j<100;j++){
      V[i][j]=0;
      cnt[j]=0;
      d[j]=0;
      f[j]=0;
      come[j]=0;
    }
  }
  //グラフ情報の読み込み
 int  m=0;
  for(int i=0;i<n;i++){
    cin>>u;
    cin>>k;
    for(int j=0;j<k;j++){
      cin>>v;
      V[u-1][m]=v;
      m++;
    }
    m=0;
  }


  //スタートは0
 d[0]=1;
 time++;
  while(1){

    if(time==2*n+1) break;
    //先がありかつそこは探索終了していない
    if(V[l][cnt[l]]!=0 && f[V[l][cnt[l]]-1]==0){ 
     
      if(d[V[l][cnt[l]]-1]==0) d[V[l][cnt[l]]-1]=time;

   come[V[l][cnt[l]]-1]=l;
      cnt[l]++;
      l=V[l][cnt[l]-1]-1; 

      time++;
      //先がないまたはさきが探索終了している
    }else{

      if(d[l]==0) d[l]=time;
       f[l]=time;
      l=come[l];
      time++;

    }

  }
  /*
  for(int i=0;i<n;i++){
    for(int j=0;j<n;j++){
    cout<<V[i][j]<<" ";
    if(j==n-1) cout<<endl;
  }
  }
  */
  //出力
  for(int i=0;i<n;i++){

    cout<<i+1<<" "<<d[i]<<" "<<f[i]<<endl;
    }


  return 0;
}

C++: #include <stdio.h>

int time, n;
int d[100], f[100], color[100];

void dfs(int u) {
    color[u] = 1
    d[u] = ++time;
    for (int i=0; i<n; i++) {
        if(M[u][i] && color[i] == 0) {
            dfs(i);
        }
    }
    color[u] = 2;
    f[u] = ++time;
}

void dfs_init(){
    for (int i=0; i<100; i++) color[i] = 0;
    dfs();
}

int main() {
    int u, k, v;
    scanf("%d", &n);
    
    int M[n][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++) {
        scanf("%d %d", &u, &k);
        for (int j=0; j<k; j++) {
            scanf("%d", &v);
            M[u-1][v-1] = 1;
        }
    }
    
    dfs_init();
    
    for (int i=0; i<n; i++) {
        printf("%d %d %d\n", i, d[i], f[i]);
    }
    return 0;
}

C++: #include <cstdio>
#include <stack>
#include <vector>
using namespace std;
static const int MAX = 101;
int V, tt;
bool visited[MAX];
int disc[MAX], finish_time[MAX];
vector<int> G[MAX];

void dfs(int current) {
      visited[current] = true;
      disc[current] = ++tt;
      for (int i = 0; i < G[current].size(); i++) {
          int next = G[current][i];
          if (!visited[next]) dfs(next);
      }
      finish_time[current] = ++tt;
}

int main()
{
    int k, source, target;
    tt=0;
    scanf("%d", &V);
    for (int i = 0; i < V; i++) {
        scanf("%d %d", &source, &k);
        for (int j = 0; j < k; j++) {
            scanf("%d", &target);
            G[source].push_back(target);
        }
    }

    fill(visited, visited+V+1, 0);
    fill(disc, disc+V+1, 0);
    fill(finish_time, finish_time+V+1, 0);
    for (int i = 1; i <= V; i++) {
        if (!visited[i]) {
            dfs(i);
        }
    }

    for (int i = 1; i <=V; i++) {
        printf("%d %d %d\n", i, disc[i], finish_time[i]);
    }

    return 0;
}

C++: /*
** dfs 遍历图
*/

# include <cstdio>
# include <cstring>
# include <stack>
using namespace std;

const int MAX = 100 + 2;

int g[MAX][MAX], d[MAX], f[MAX], c[MAX], n, t;

void init() {
    memset(g, 0, sizeof(g));
    memset(d, 0, sizeof(d));
    // memset(f, 0, sizeof(f));
    memset(c, 0, sizeof(c));
    scanf("%d", &n);
    int u, v, k;
    for (int i = 1; i <= n; i++) {
        scanf("%d%d", &u, &k);
        while (k--) {
            scanf("%d", &v);
            g[u][v] = 1;
        }
    }

    t = 0;
}

void dfs(int u) {
    t++;
    stack<int> s;
    s.push(u);
    int node;
    d[u] = t;
    c[u] = 1;

    while(!s.empty()) {
        t++;
        node = s.top();
        int p = 1;
        for (; p <= n; p++) {
            if (g[node][p] != 0 && c[p] == 0) {
                s.push(p);
                d[p] = t;
                c[p] = 1;
                break;
            }
        }
        if (p > n) {
            f[node] = t;
            s.pop();
        }
    }
}

void solve() {
    init();
    for (int i = 1; i <= n; i++) {
        if (c[i] == 0) {
            dfs(i);
        }
    }
    for (int i = 1; i <= n; i++) {
        printf("%d %d %d\n", i, d[i], f[i]);
    }
}

int main() {
    // freopen("infile", "r", stdin);
    // freopen("outfile", "w", stdout);
    solve();
    return 0;
}