Go: package main

import (
	"fmt"
)

func main() {
	var n int
	fmt.Scan(&n)
	g := make([][]int, n+1)
	for i := 0; i < n; i++ {
		var u,k int
		fmt.Scan(&u)
		fmt.Scan(&k)
		g[u] = make([]int, k)
		for j := 0; j < k; j++ {
			fmt.Scan(&g[u][j])
		}
	}

	d := make([]int, n+1)
	f := make([]int, n+1)
	dfs(&g, &d, &f, 1, 1)

	for i := 1; i <= n; i++ {
		fmt.Printf("%d %d %d\n", i, d[i], f[i])
	}
}

func dfs(g *[][]int, d *[]int, f *[]int, id int, t int) int {
	if (*d)[id] > 0 {
		return t
	}
	(*d)[id] = t
	t += 1
	for i := 0; i < len((*g)[id]); i++ {
		t = dfs(g, d, f, (*g)[id][i], t)
	}
	(*f)[id] = t
	return t+1
}

C++: #include <bits/stdc++.h>
using namespace std;
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define rep(i,n)   FOR(i,0,n)
#define pb emplace_back
typedef long long ll;
typedef pair<int,int> pint;

vector<int> g[101];
bool used[101];
pint ans[101];
int cnt;
void dfs(int v){
    used[v]=true;
    ans[v].first=cnt++;
    rep(i,g[v].size()){
        if(!used[g[v][i]]){
            dfs(g[v][i]);
        }
    }
    ans[v].second=cnt++;
}
int main(){
    int n,u,k,v;
    cin>>n;
    rep(i,n){
        cin>>u>>k;
        --u;
        rep(j,k){
            cin>>v;
            --v;
            g[u].pb(v);
        }
    }
    cnt=1;
    rep(i,n){
        if(!used[i]) dfs(i);
    }
    rep(i,n) cout<<i+1<<" "<<ans[i].first<<" "<<ans[i].second<<endl;
    return 0;
}

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

int a[101][101];
int n=0;
int found[101];
int ended[101];
int aaa(int i, int time);

int main(){
  for(int i=0; i<101; i++)
    for(int j=0; j<101; j++)
      a[i][j]=0;
  int u, k, v;
  cin>>n;
  for(int i=0; i<n; i++){
    cin>>u>>k;
    for(int j=0; j<k; j++){
      cin>>v;
      a[u][v]=1;
    }
  }

  int time=0;
  for(int i=0; i<101; i++){
    found[i]=0;
    ended[i]=0;
  }

  for(int i=1; i<n+1; i++){
    if(found[i]>0)
      continue;
    time++;
    found[i]=time;
    time=aaa(i, time);
    ended[i]=time;
  } 

  for(int i=1; i<n+1; i++)
    cout<<i<<' '<<found[i]<<' '<<ended[i]<<endl;
}

int aaa(int i, int time){
  for(int k=1; k<n+1; k++){
    if(a[i][k]==1&&found[k]==0){
      time++;
      found[k]=time;
      time=aaa(k, time);
      ended[k]=time;
    } 
  }
  time++;
  return time;
}

C++: #include "bits/stdc++.h"
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];
int color[N],d[N],f[N],tt;
int nt[N];

//u?????£??\??????v?????????????????????
int next(int u){
	for (int v = 0; 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;
	//????¨???????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();
	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, 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() {

  cin >> n;
  for (int i = 0; i < n; i++) {
    for (int j = 0; j < n; j++) {
      M[i][j] = 0;
    }
  }

  int u, k, v;
  for (int i = 0; i < n; i++) {
    cin >> u >> k;
    u--; // to 0 origin
    for (int j = 0; j < n; j++) {
      cin >> v;
      v--; // to 0 origin
      M[u][v] = 1;
    }
  }

  dfs();

  return 0;
}

C++: #include <bits/stdc++.h>
#define LOOP(n) for (int _i = 0; _i < (n); _i++)
#define REP(i, n) for (int i = 0; i < (n); ++i)
#define RREP(i, n) for (int i = (n); i >= 0; --i)
#define FOR(i, r, n) for (int i = (r); i < (n); ++i)
#define ALL(obj) begin(obj), end(obj)
using namespace std;
using ll = long long;
using ull = unsigned long long;

const int INF = 2100100100;
const int MOD = 1e9 + 7;

// 多次元 vector 生成
template <class T>
vector<T> make_vec(size_t a) {
    return vector<T>(a);
}
template <class T, class... Ts>
auto make_vec(size_t a, Ts... ts) {
    return vector<decltype(make_vec<T>(ts...))>(a, make_vec<T>(ts...));
}
template <class T>
bool chmax(T &a, const T &b) {
    if (a < b) {
        a = b;
        return 1;
    }
    return 0;
}
template <class T>
bool chmin(T &a, const T &b) {
    if (b < a) {
        a = b;
        return 1;
    }
    return 0;
}

using Graph = vector<vector<int>>;

int N, M, K, Q;
int t;
int used[200];
void dfs(const Graph &G, vector<tuple<int, int, int>> &ans, int node) {
    t++;
    int d = t;
    used[node] = 1;
    for (auto v : G[node]) {
        if (used[v] == 0) {
            dfs(G, ans, v);
        }
    }
    t++;
    int f = t;
    ans.push_back(make_tuple(node, d, f));
}

int main() {
    // cin.tie(0);
    // ios::sync_with_stdio(false);

    cin >> N;
    Graph G(N);
    memset(used, 0, sizeof(used));
    REP(i, N) {
        int u, k;
        cin >> u >> k;
        u--;
        REP(j, k) {
            int v;
            cin >> v;
            v--;
            G[i].push_back(v);
        }
        sort(ALL(G[i]));
    }

    vector<tuple<int, int, int>> ans;
    t = 0;
    REP(u, N) {
        if (used[u] != 1) {
            dfs(G, ans, u);
        }
    }
    sort(ALL(ans));

    REP(i, (int)ans.size()) { cout << get<0>(ans[i]) + 1 << " " << get<1>(ans[i]) << " " << get<2>(ans[i]) << endl; }

    return 0;
}