Go: package main

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

// I/O
type Scanner struct {
	sc *bufio.Scanner
}

func NewScanner() *Scanner {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)
	sc.Buffer(make([]byte, 1024), int(1e+9))
	return &Scanner{sc}
}

func (s *Scanner) nextStr() string {
	s.sc.Scan()
	return s.sc.Text()
}

func (s *Scanner) nextInt() int {
	i, e := strconv.Atoi(s.nextStr())
	if e != nil {
		panic(e)
	}
	return i
}

func (s *Scanner) nextFloat() float64 {
	f, e := strconv.ParseFloat(s.nextStr(), 64)
	if e != nil {
		panic(e)
	}
	return f
}

func (s *Scanner) nextRuneSlice() []rune {
	return []rune(s.nextStr())
}

func (s *Scanner) nextIntSlice(n int) []int {
	res := make([]int, n)
	for i := 0; i < n; i++ {
		res[i] = s.nextInt()
	}
	return res
}

func (s *Scanner) nextFloatSlice(n int) []float64 {
	res := make([]float64, n)
	for i := 0; i < n; i++ {
		res[i] = s.nextFloat()
	}
	return res
}

// Arithmetic
func max(nums ...int) int {
	m := nums[0]
	for _, i := range nums {
		if m < i {
			m = i
		}
	}
	return m
}

func min(nums ...int) int {
	m := nums[0]
	for _, i := range nums {
		if m > i {
			m = i
		}
	}
	return m
}

func abs(x int) int {
	if x > 0 {
		return x
	}
	return -x
}

func pow(x, y int) int {
	res := 1
	for i := 0; i < y; i++ {
		res *= x
	}
	return res
}

func ceil(a, b int) int {
	if a%b == 0 {
		return a / b
	} else {
		return a/b + 1
	}
}

// Sort
type RuneSlice []rune

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

// Main
func main() {
	sc := NewScanner()
	wtr := bufio.NewWriter(os.Stdout)
	N := sc.nextInt()
	G := make([][]int, N)
	for i := 0; i < N; i++ {
		u, k := sc.nextInt()-1, sc.nextInt()
		for j := 0; j < k; j++ {
			G[u] = append(G[u], sc.nextInt()-1)
		}
	}
	ans := make([][2]int, N)
	time := 0
	found := make(map[int]bool)
	var dfs func(cur int)
	dfs = func(cur int) {
		time++
		ans[cur][0] = time
		found[cur] = true
		for i := 0; i < len(G[cur]); i++ {
			next := G[cur][i]
			if !found[next] {
				dfs(G[cur][i])
			}
		}
		time++
		ans[cur][1] = time
	}
	for i := 0; i < N; i++ {
		if !found[i] {
			dfs(i)
		}
	}

	for i := 0; i < N; i++ {
		fmt.Fprint(wtr, i+1)
		for j := 0; j < 2; j++ {
			fmt.Fprint(wtr, " ")
			fmt.Fprint(wtr, ans[i][j])
		}
		fmt.Fprintln(wtr)
	}
	wtr.Flush()
}

C++: #include <iostream>
#include <algorithm> // next_permutation
#include <iomanip>
#include <cmath>
#include <vector>
#include <sstream>
#include <string>
#include <cstdio>
#include <stack>
#include <queue>
#include <list>
#include <numeric> //accumulate
//#include <unordered_map> //???????????\??¢??°
#include <fstream> //ifstream, ofstream

//#define NDEBUG //NDEBUG???#include <cassert>???????????????????????????????????´???assert?????????????????????????????????NDEBUG?????????????????????????????????????????????
#include <cassert> //assert


using namespace std;

//???????????°??????TEST????????????????????¬???????????????????????????????????¢????????????
#define TEST //*******************************************************************************************************************************************
//?????????????????¨??§?????\????????????????????????????????°?????????????¨???????????????????dout???????????????????????§???????????¬??????????????????????????????????????????
//??????????????????????????????????????????????????????????§?CPU???????£??????????????????§???TLE?????????????????????????????????????????§????????¨???                           ????????????????????????cerr????????£????????????????????????????????????
#ifdef TEST
#define dout cout
#define din cin
#else
stringstream dummy; //???????????°??????dout?????????????????????????????????
#define dout dummy.str(""); dummy.clear(stringstream::goodbit); dummy //dummy?????????????????????????????????????????¨?????¢?????¢???????????????
//???????????¨??????????????????goodbit?????????????????????????????¨???????????´????????????????????????????????¨?????°?????????????????§???????????????????????????????????? http://d.hatena.ne.jp/linden/20060427/p1
#endif

//?¨??????????????????????????????????????????????????????´??????OUTPUTFILE????????????????????¬???????????????????????????????????¢????????????
//#define OUTPUTFILE "output.txt" //*******************************************************************************************************************************************
#ifdef OUTPUTFILE
#define dout outputfile //??¨????????????TLE????????§?????????dout?????¨??¨??????????????¢????????????????????????????????????????????§????¨????????????´??????????????£??????????????????????¨?????????????????????????????????????????????§?????????????????????
ofstream outputfile(OUTPUTFILE);
#define OutputFilePath "/Users/Nag/Documents/Prgm/Test/DerivedData/Test/Build/Products/Debug/output.txt"
#endif

//?¨??????\???????????????????????????????????????????????´??????INPUTFROMTEXTFILE????????????????????¬???????????????????????????????????¢????????????
//#define INPUTFILE "input.txt" //*******************************************************************************************************************************************
#ifdef INPUTFILE
#define din inputfile
ifstream inputfile(INPUTFILE);
#endif


#define disp(A) dout << #A << " = " << (A) << endl
#define disP(A) dout << setw(3) << (A) << " " // << setw(3) ??????????????\????????????
#define rep(i,a,n) for(int (i)=(a); (i)<(n); (i)++)
#define dispAll(A,n) dout << #A << " = "; rep(j, 0, (n)) {disP(A[j]);} dout << endl

typedef pair<int,int> pii;
typedef vector<int> vi;
typedef unsigned long long ll;


const int INF = 999;//1e9-1;

int n;

//all array 1-based index
bool adjacencyMatrix[101][101] = {0};
int adjacencyList[101][101] = {0};

int currentTime = 1;
int discoveredTime[101] = {0};
int finishedTime[101] = {0};

int currentNode = 1;


void visit(int i) {
//    disp(src); disp(i);
//    dispAll(discoveredTime, n+3);
//    dispAll(finishedTime, n+3);
    
    if(discoveredTime[i]!=0) return;
    
    discoveredTime[i]=currentTime++;
    
    int j = 1;
    while(adjacencyList[i][j] != 0) {
//        disp(j);
//        disp(adjacencyList[i][j]);
        
        assert(j<=n);
        //??????????????¨??¨??§n?????§??????????????¨??????????????¨??????????????????list????????§??§???n-1??????????????°???????????§???0???n-1?????§???????????°??????adjacencyList[i][n]????????¶???0???????????????
        
        visit(adjacencyList[i][j]);
        j++;
    }
    
    finishedTime[i] = currentTime++;
    
    return;
}



int main() {
    din>>n;
    
    int s, g, numOfAdjacent;
    
    
    //input
    rep(i,1,n+1) {
        din>>s>>numOfAdjacent;
        
        rep(j,1,numOfAdjacent+1) {
            din>>g;
            adjacencyMatrix[s][g] = 1;
            adjacencyList[s][j] = g;
        }
    }
    
//    //test display
//    dout<<"   dist = ";
//    rep(j,1,n+1) dout<<j<<" ";
//    dout<<endl;
//    dout<<"          ";
//    rep(j,1,n+1) dout<<"-"<<" ";
//    dout<<endl;
//    
//    rep(i,1,n+1) {
//        dout<<"src = "<<i<<" | ";
//        rep(j,1,n+1) {
//            dout<<(j==1?"":" ")<<adjacencyMatrix[i][j];
//        }
//        dout<<endl;
//    }
//    
//    dout<<endl;
//    dout<<"                       ";
//    rep(j,0,n+1) disP(j);
//    dout<<endl;
//    dout<<"                       ";
//    rep(j,0,n+1) dout<<"  - ";
//    dout<<endl;
//    rep(i,1,n+1) {
//        disP(i); dispAll(adjacencyList[i], n+1);
//    }
    
    
    
    //DFS (Depth First Search)
    rep(i,1,n+1) {
        if(discoveredTime[i]==0) visit(i);
    }

//    dispAll(discoveredTime, n+1);
//    dispAll(finishedTime, n+1);
    
    
    //output
    rep(i,1,n+1) {
        dout<<i<<" "<<discoveredTime[i]<<" "<<finishedTime[i]<<endl;
    }
    
    
#ifdef INPUTFILE
    inputfile.close();
#endif
    
#ifdef OUTPUTFILE
    outputfile.close();
    cout << "\"" << OutputFilePath << "\"" << endl;
#endif
    
    return 0;
}