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 <iostream>
#include <vector>
#include <algorithm>

void dfs(int start, int n, int& time, std::vector<std::vector<int> >& G, std::vector<int>& D, std::vector<int>& F)
{
	D.at(start) = ++time;
	if (G.at(start).size() == 0)
	{
		F.at(start) = ++time;
		return;
	}
	for (int i = 0; i < G.at(start).size(); i++)
	{
		if (D.at(G.at(start).at(i)) == 0)
			dfs(G.at(start).at(i), n, time, G, D, F);
	}
	F.at(start) = ++time;
}


int main()
{	
	int n;
	std::cin >> n;
	std::vector<std::vector<int> > G;
	for (int i = 0; i < n; i++)
	{
		int nl;
		int m;
		std::vector<int> V;
		std::cin >> nl >>  m;
		for (int j = 0; j < m; j++)
		{
			int v;
			std::cin >> v;
			v--;
			V.push_back(v);
		}
		G.push_back(V);
	}
	std::vector<int> D(n, 0);
	std::vector<int> F(n, 0);
	int time = 0;
	for (int i = 0; i < n; i++)
	{
		if (D.at(i) == 0)
			dfs(i, n, time, G, D, F);	
	}
	
	for (int i = 0; i < n; i++)
	{
		std::cout << i + 1 << ' ' << D.at(i) << ' ' << F.at(i) << '\n';
	}
	return 0;
}

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

void dfs(int cur);

int A[100][100], d[100], f[100];;
int n,t=0;

int main()
{
    	cin>>n;
        
    	for(int i=0;i<n;++i){

		d[i]=0;
		f[i]=0;

        	for(int j=0;j<n;++j){
            		A[i][j]=0;
        	}
        
        	int m,k; //k=number of adj
        	cin>>m>>k;
        	assert(m==i+1);
        
        	for(int j=0;j<k;++j){
            		int adj;
            		cin>>adj;
            		if(adj){
                		A[i][adj-1]=1;
            		}
        	}
    	}

	/*
	for(int i=0;i<n;++i){
		for(int j=0;j<n;++j){
			cout<<A[i][j]<<" ";
		}
		cout<<endl;
	}
	*/

	for(int i=0;i<n;++i){
		if(d[i]==0) dfs(i);
	}

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

    	return 0;
}

void dfs(int cur)
{
	t+=1;
	d[cur]=t;
	//cout<<"visiting "<<cur+1<<" "<<t<<endl;

	for(int dst=0;dst<n;++dst){
		if(A[cur][dst]==1&&d[dst]==0){
			dfs(dst);
		}
	}

	t+=1;
	f[cur]=t;

	//cout<<"leaving "<<cur+1<<" "<<t<<endl;

	return;
}

C++: #include <cstdio>
using namespace std;
#define MAX_N 100

int graph[MAX_N+1][MAX_N+1];
int d[MAX_N+1];
int f[MAX_N+1];

int n;
int t;
void dfs(int id) {
  if(id != 0)
    t++;
  d[id] = t;
  for(int i=1;i<=n;i++) {
    if(graph[id][i] != 0 && d[i] == 0) {
      dfs(i);
    }
  }
  if(id != 0)
    t++;
  f[id] = t;
}

int main() {
  scanf("%d\n",&n);
  // dummy
  for(int i=0;i<=n;i++) {
    graph[0][i] = 1;
  }
  int u,k,v;
  for(int i=0;i<n;i++) {
    scanf("%d %d ",&u,&k);
    for(int j=0;j<k;j++) {
      scanf("%d ",&v);
      graph[u][v] = 1;
    }
  }

  dfs(0);

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

C++: // 274
#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
#include <stack>
using namespace std;

int N;
int G[110][110] = {}; // 隣接リスト表現
int d[101] = {};
int f[101] = {};

int main(void) {

    cin >> N;

    for (int i = 1; i <= N; ++i) {
        int v;
        cin >> v;
        cin >> G[v][0];
        for (int k = 1; k <= G[v][0]; ++k) {
            cin >> G[i][k];
        }
    }

    int time = 0;
    for (int n = 1; n <= N; ++n) {
        if (d[n] == 0) {
            stack<int> S;

            S.push(n);
            
            d[n] = ++time;
            while (!S.empty()) {
                int u = S.top();

                bool found = false;
                // 未探索の奴をスタックに積む
                for (int i = 0; i < G[u][0]; ++i) {
                    if (d[G[u][i + 1]] != 0) continue;
                    S.push(G[u][i + 1]);
                    found = true;
                    d[G[u][i + 1]] = ++time;
                    break;
                }

                if (!found) {
                    f[u] = ++time;
                    S.pop();
                } 
            }
        }
    }


    for (int i = 1; i <= N; ++i) {
        cout << i << ' ' << d[i]  << ' ' << f[i] << endl;
    }
    return 0;
}

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

static const int MAX_NUM = 101;

static const int NO_VISIT  = 0;
static const int NOW_VISIT = 1;
static const int END_VISIT = 2;

void DSF(int* matrix, int num)
{
    int i, j;
    int ttime = 0;
    int stime[MAX_NUM+1] = {0};
    int etime[MAX_NUM+1] = {0};
    int state[MAX_NUM+1] = {0};
    stack<int> S;
    int target, next;
    int *tmp;

    for (j = 1; j <= num; j++) {
    if (state[j] != NO_VISIT) {
        continue;
    }
    S.push(1);
    ++ttime;
    stime[1] = ttime;
    state[1] = NOW_VISIT;

    while (S.empty() == false) {
        target = S.top();
        for (i = 1; i <= num; i++) {
            tmp = matrix + MAX_NUM * target + i;
            if ((*tmp == 1) && (state[i] == NO_VISIT)) {
                *tmp = 2;
                S.push(i);
                ++ttime;
                stime[i] = ttime;
                state[i] = NOW_VISIT;
                break;
            }
        }

        if (i == num + 1) {
            S.pop();
            ++ttime;
            etime[target] = ttime;
            state[target] = END_VISIT;
        }
    }
    }

    for (i = 1; i <= num; i++) {
        printf("%d %d %d\n", i, stime[i], etime[i]);
    }

    return;
}

int main(void)
{
    int i, j;
    int num;
    int elem;
    int nume;
    int tmp;
    int matrix[MAX_NUM][MAX_NUM] = {0};

    scanf("%d", &num);

    for (i = 0; i < num; i++) {
        scanf("%d %d", &elem, &nume);
        for (j = 0; j < nume; j++) {
            scanf("%d", &tmp);
            matrix[elem][tmp] = 1;
        }
    }

    DSF(&matrix[0][0], num);

    return 0;
}