Go: package main

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

type TimeRecord struct {
	discoverTime int
	finishTime   int
}

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

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

	timeRecordMap := make([]TimeRecord, n)
	childrenMap := make([][]int, n)
	for i := 1; i <= n; i++ {
		node, err := nextInt(sc)
		if err != nil {
			panic(err)
		}
		timeRecordMap[node-1] = TimeRecord{-1, -1}

		childNum, err := nextInt(sc)
		if err != nil {
			panic(err)
		}
		childrenMap[node-1] = make([]int, childNum)
		for j := 0; j < childNum; j++ {
			child, err := nextInt(sc)
			if err != nil {
				panic(err)
			}
			childrenMap[node-1][j] = child
		}
	}

	timer := 1
	startNode := 1
	for {
		visit(startNode, &timer, childrenMap, timeRecordMap)
		startNode = findStartNode(childrenMap, timeRecordMap)
		if startNode < 0 {
			break
		}
	}
	for k, v := range timeRecordMap {
		fmt.Printf("%d %d %d\n", k+1, v.discoverTime, v.finishTime)
	}
}

func findStartNode(childrenMap [][]int, timeRecordMap []TimeRecord) int {
	x := -1
	for node, timeRecord := range timeRecordMap {
		if timeRecord.discoverTime < 0 {
			x = node + 1
			break
		}
	}
	return x
}

func visit(currentNode int, timer *int, childrenMap [][]int, timeRecordMap []TimeRecord) {
	if timeRecordMap[currentNode-1].discoverTime > 0 {
		return
	}
	children := childrenMap[currentNode-1]
	timeRecordMap[currentNode-1] = TimeRecord{*timer, timeRecordMap[currentNode-1].finishTime}
	(*timer)++
	for i := 0; i < len(children); i++ {
		visit(children[i], timer, childrenMap, timeRecordMap)
	}
	timeRecordMap[currentNode-1] = TimeRecord{timeRecordMap[currentNode-1].discoverTime, *timer}
	(*timer)++
}

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

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

int N;
const int maxn = 105;
const int WHITE = 0;
const int BLACK = 2;
int G[maxn][maxn];
vector<int> color;
vector<int> startTime;
vector<int> endTime;
vector<int> nt;

int getNext(int u){
    int res = -1;
    for(int i = nt[u];i<N;i++){
        if(G[u][i] && color[i]==WHITE){
            res = i;
            nt[u] = i;
            break;
        }
    }
    return res;
}

void DFS(int u,int &time){
    if(color[u]!=WHITE) return;
    stack<int> nodeStack;
    nodeStack.push(u);
    startTime[u] = time++;
    while(!nodeStack.empty()){
        int u = nodeStack.top();
        //if(color[u]!=WHITE) continue;
        color[u] = BLACK;

        int v = getNext(u);
        if(v!=-1){
            startTime[v] = time++;
            nodeStack.push(v);
            continue;
        }
        else{
            endTime[u] = time++;
            nodeStack.pop();
        }
    }
}

int main(){
    //freopen("data.txt","r",stdin);
    memset(G,0,sizeof(G));
    cin >> N;
    color.resize(N,WHITE);
    startTime.resize(N,0);
    endTime.resize(N,0);
    nt.resize(N,0);
    int u,k;
    for(int i = 0;i<N;i++){
        scanf("%d %d",&u,&k);
        u--;
        for(int j = 0;j<k;j++){
            int v;
            scanf("%d",&v);
            v--;
            G[u][v] = 1;
        }
    }
    int time = 1;
    for(int i = 0;i<N;i++) if(color[i]==WHITE) DFS(i,time);
    for(int u = 0;u<N;u++){
        printf("%d %d %d\n",u+1,startTime[u],endTime[u]);
    }
    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++) {
		if(M[u][v] == 1) return v;
		nt[u] = v + 1;
	}
	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[u] = BLACK;
		   S.pop();
		   f[u] = ++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;
	tt = 0;
	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;
}