Go: package main

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

//util
var sc = bufio.NewScanner(os.Stdin)

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

func nextInt() int {
	sc.Scan()
	i, e := strconv.Atoi(sc.Text())
	if e != nil {
		panic(e)
	}
	return i
}

func printList(list []int) {
	n := len(list)
	buf := bufio.NewWriter(os.Stdout)
	for _, v := range list[0 : n-1] {
		buf.Write([]byte(fmt.Sprintf("%d ", v)))
	}
	buf.Write([]byte(fmt.Sprintf("%d\n", list[n-1])))
	buf.Flush()
}

func max(a, b int) int {
	if a > b {
		return a
	} else {
		return b
	}
}

func min(a, b int) int {
	if a > b {
		return b
	} else {
		return a
	}
}

//solve

const MAX = 100
const WHITE = 0
const GRAY = 1
const BLACK = 2

var time, n int

//隣接行列
var M [MAX][MAX]int

//d[i]: 最初にiを訪問した時刻。発見時刻
//f[i]: iの隣接リストを訪問し終えた時刻。完了時刻
var color, d, f [MAX]int

func dfs_visit(u int) {
	color[u] = GRAY
	time++
	d[u] = time
	//隣接を調べる
	for v := 0; v < n; v++ {
		if M[u][v] == 0 {
			continue
		}
		//隣接するvが、未訪問だった場合
		if color[v] == WHITE {
			dfs_visit(v)
		}
	}
	//訪問完了処理
	color[u] = BLACK
	time++
	f[u] = time
	//訪問完了
}

func dfs() {
	//初期化
	for u := 0; u < n; u++ {
		color[u] = WHITE
	}
	time = 0

	//未訪問のuを始点として、深さ優先探索
	for u := 0; u < n; u++ {

		if color[u] == WHITE {
			dfs_visit(u)
		}
	}

	for u := 0; u < n; u++ {
		fmt.Println(u+1, d[u], f[u])
	}
}

func main() {
	sc.Split(bufio.ScanWords)
	n = nextInt()
	for i := 0; i < n; i++ {
		u, k := nextInt(), nextInt()
		M[u-1][u-1] = 0

		//fmt.Println(u, k)
		if k > 0 {
			for j := 0; j < k; j++ {

				v := nextInt()
				M[u-1][v-1] = 1

			}
		}

	}

	dfs()

}

C++: #include <bits/stdc++.h>

using namespace std;

int main() {
  int n;
  cin >> n;

  vector<vector<int>> adjacent(n);
  for (int i = 0; i < n; i++) {
    int u, k;
    cin >> u >> k;
    --u;

    for (int i = 0; i < k; i++) {
      int v;
      cin >> v;
      --v;

      adjacent[u].push_back(v);
    }
  }

  vector<int> d(n, 0), f(n, 0);
  vector<bool> visited(n, false);
  stack<int> S;

  S.push(0);

  int t = 1;

  d[0] = t;

  while (!S.empty()) {
    ++t;

    int u = S.top();

    if (!visited[u]) {
      visited[u] = true;
    }

    bool done = true;
    for (int i = 0; i < adjacent[u].size(); i++) {
      int v = adjacent[u][i];

      if (!visited[v]) {
        done = false;
        d[v] = t;
        S.push(v);
        break;
      }
    }

    if (done) {
      f[u] = t;
      S.pop();
    }

    // スタックが空になった後、未訪問なノードがあればそれを始点として再度DFSする
    if (S.empty()) {
      for (int i = 0; i < n; i++) {
        if (!visited[i]) {
          ++t;
          S.push(i);
          d[i] = t;
          break;
        }
      }
    }
  }

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

  return 0;
}

/*
6
1 2 2 3
2 2 3 4
3 1 5
4 1 6
5 1 6
6 0
*/

C++: #include <cstdint>
#include <vector>

using namespace std;

#define GRAPH_SIZE 101
#define START_INDEX 1

enum color_t {
  WHITE,
  GRAY,
  BLACK,
};

static uint32_t t = 0;
static color_t state[GRAPH_SIZE];
static vector<uint32_t> graph[GRAPH_SIZE];

void depth_first_search(void (*visited)(uint32_t), void (*invested)(uint32_t))
{
  for (uint32_t i = START_INDEX; i < GRAPH_SIZE; i++) {
    state[i] = WHITE;
  }

  static vector<pair<uint32_t, vector<uint32_t>>> stack;

  stack.push_back(make_pair(START_INDEX, graph[START_INDEX]));
  state[START_INDEX] = GRAY;
  t++;
  visited(START_INDEX);

  while (!stack.empty()) {
    pair<uint32_t, vector<uint32_t>> top = stack.back();
    bool found = false;
    for (uint32_t i = 0; i < top.second.size(); i++) {
      uint32_t next = top.second[i];
      if (state[next] == WHITE) {
        found = true;
        state[next] = GRAY;
        t++;
        visited(next);
        stack.push_back(make_pair(next, graph[next]));
        break;
      }
    }

    if (!found) {
      stack.pop_back();
      t++;
      state[top.first] = BLACK;
      invested(top.first);
    }
  }
}

#include <iostream>

static uint32_t visited_time[GRAPH_SIZE];
static uint32_t invested_time[GRAPH_SIZE];

static void visited(uint32_t i)
{
  visited_time[i] = t;
}

static void invested(uint32_t i)
{
  invested_time[i] = t;
}

int32_t main(void)
{
  uint32_t num;
  cin >> num;

  for (uint32_t i = 0; i < num; i++) {
    uint32_t index, len;
    cin >> index >> len;
    for (uint32_t j = 0; j < len; j++) {
      uint32_t val;
      cin >> val;
      graph[index].push_back(val);
    }
  }

  depth_first_search(visited, invested);

  for (uint32_t i = START_INDEX; i < (START_INDEX + num); i++) {
    cout << i << " " << visited_time[i] << " " << invested_time[i] << endl;
  }

  return 0;
}

C++: #include <iostream>
#include <stack>

using namespace std;

#define MAX 110
int num;
int matrix[MAX][MAX];
int dst[MAX];

void input(){
    cin >> num;
    for(int i=0;i<MAX;i++){
        dst[i] = -1;
        for(int j=0;j<MAX;j++){
            matrix[i][j] = 0;
        }
    }
    for(int i=1;i<=num;i++){
        int v; cin >> v;
        int tmp; cin >>tmp;
        for(int j=0;j<tmp;j++){
            int vi; cin >> vi;
            matrix[v-1][vi-1] = 1;
        }
    }
}

void dfs(){
    stack<int> S;
    S.push(0);
    dst[0] = 0;
    while(!S.empty()){
        int cur = S.top();
        S.pop();
        if(dst[cur]==-1 || dst[cur]== 0){
            for(int i=0;i<num;i++){
                if(matrix[cur][i]==1){
                    S.push(i);
                    dst[i] = dst[cur] + 1;
                }
            }
        }
        else if(dst[S.top()]+1 < dst[cur]){
            for(int i=0;i<num;i++){
                if(matrix[cur][i]==1){
                    S.push(i);
                    dst[i] = dst[cur] + 1;
                }
            }
        }
    }
    for(int i=0;i<num;i++){
        cout << i+1 << " " <<  dst[i] << endl;
    }
}

int main(){
    input();
    dfs();
}