Go: package main

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

var scanner = bufio.NewScanner(os.Stdin)

func nextString() string {
	scanner.Scan()
	return scanner.Text()
}

func nextInt() int {
	n, err := strconv.Atoi(nextString())
	if err != nil {
		fmt.Printf("strconv.Atoi failed: %v\n", err)
	}
	return n
}

var infty = 1000000000

type nodeKey int

type DirectedGraphNode struct {
	key       nodeKey
	adjacents []*DirectedGraphNode
	visited   bool
	d         int
	f         int
	parent    *DirectedGraphNode
}

type DirectedGraph struct {
	nodes []*DirectedGraphNode
}

func (g *DirectedGraph) setAdjacency(l, r nodeKey) {
	g.nodes[l].adjacents = append(g.nodes[l].adjacents, g.nodes[r])
}

func newDirectedGraph(nNodes int) *DirectedGraph {
	graph := DirectedGraph{}
	graph.nodes = make([]*DirectedGraphNode, nNodes)
	for iNodes := 0; iNodes < nNodes; iNodes++ {
		graph.nodes[iNodes] = &DirectedGraphNode{}
		graph.nodes[iNodes].key = nodeKey(iNodes)

		graph.nodes[iNodes].visited = false
		graph.nodes[iNodes].d = infty
		graph.nodes[iNodes].f = infty
		graph.nodes[iNodes].parent = nil
	}
	return &graph
}

type QueueEntry struct {
	node *DirectedGraphNode
	next *QueueEntry
}

type Queue struct {
	head, tail *QueueEntry
}

func (q *Queue) enqueue(node *DirectedGraphNode) {
	entry := QueueEntry{}
	entry.node = node

	if q.tail == nil {
		q.head = &entry
		q.tail = &entry
		return
	}

	q.tail.next = &entry
	q.tail = q.tail.next
}

func (q *Queue) dequeue() *QueueEntry {
	if q.head == nil {
		return nil
	}
	poped := q.head
	q.head = q.head.next
	if q.head == nil {
		q.tail = nil
	}
	return poped
}

func (q *Queue) isEmpty() bool {
	return q.head == nil
}

var time = 0

func fillDistancesByDepthFirstSearch(g *DirectedGraph) {
	for _, u := range g.nodes[1:] {
		if !u.visited {
			dfsVisit(g, u)
		}
	}
}

func dfsVisit(g *DirectedGraph, u *DirectedGraphNode) {
	time++
	u.d = time

	u.visited = true
	for _, v := range u.adjacents {
		if !v.visited {
			v.parent = u
			dfsVisit(g, v)
		}
	}
	time++
	u.f = time
}

func main() {
	scanner.Split(bufio.ScanWords)

	nNodes := nextInt()
	g := newDirectedGraph(nNodes + 1)

	for iNode := 0; iNode < nNodes; iNode++ {
		nodeKeyLeft := nodeKey(nextInt())
		nAdj := nextInt()
		for iAdj := 0; iAdj < nAdj; iAdj++ {
			nodeKeyRight := nodeKey(nextInt())
			g.setAdjacency(nodeKeyLeft, nodeKeyRight)
		}
	}

	fillDistancesByDepthFirstSearch(g)

	for iNode := 1; iNode <= nNodes; iNode++ {
		node := g.nodes[iNode]
		fmt.Println(node.key, node.d, node.f)
	}
}

C++: 
#include <iostream>
#include <string>
#include <vector>
#include <queue>
#include <cstring>
#include <stack>
#define fre freopen("//home//yanjiewei//CLionProjects//cin.txt", "r", stdin)


using namespace std;

int map[105][105], vis[105];
stack <int> s;

int main(){
//    fre;
    memset(map, 0, sizeof(map));
    memset(vis, 0, sizeof(vis));
    int n;
    cin>> n;
    int u, k, v;
    for(int i = 0; i < n; i++){
        cin>> u;
        cin>> k;
        while(k--){
            cin>> v;
            map[u][v] = 1;
        }
    }
    int t = 1, now = 1;
    int d[105], f[105];
    s.push(1), d[1] = t, vis[1] = 1;
    while(!s.empty()){
        int p = 0;
        now = s.top();
        for(int i = 1; i <= n; i++){
            if(map[now][i] == 1 && vis[i] == 0) {
                s.push(i);
                t++, d[i] = t;
                vis[i] = 1;
                p++;
                break;
            }
        }
        if(p == 0){
            int out = s.top();
            s.pop();
            t++, f[out] = t;
        }
    }
    for(int i = 1; i <= n; i++){
        cout<< i<< ' '<< d[i]<< ' '<< f[i]<< endl;
    }
    return 0;
}

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

using namespace std;
#define rep(i,n) for(int i=0; i<(n); i++)
#define REP(i,a,b) for(int i=(a); i<(b); i++)
#define INF 1000000007
typedef int64_t in;
typedef long long ll;

int n;
int m[105][105] = {};
int color[105] = {};
int d[105] = {};
int f[105] = {};
int u,k;
int v;
int t=0;
int nt[105] = {};

int next(int u){
    REP(v, nt[u], n){
        nt[u] = v + 1;
        if(m[u][v]) return v;
    }
    return -1;
}

void dfs(int u){
    rep(u,n){
        if(color[u] == 0){
            stack<int> S;
            color[u] = 1;
            d[u] = ++t;
            S.push(u);

            while(!S.empty()){
                u = S.top();
                v = next(u);
                if(v != -1){
                    if(color[v] == 0){
                        S.push(v);
                        color[v] = 1;
                        d[v] = ++t;
                    }
                }else{
                    S.pop();
                    color[u] = 2;
                    f[u] = ++t;
                }
                
            }
        }
    }

    rep(i,n){
        cout << i+1 << " " << d[i] << " " << f[i] << endl;
    }
}

int main(){
    cin >> n;
    
    /*rep(i,n){
        color[i] = 0;
    }*/

    rep(i,n){
        cin >> u >> k;
        for(int i=0; i<k; i++){
            cin >> v;
            m[u-1][v-1] = 1;
        }
    }

    dfs(0);
}

C++: #include <iostream>
#include <set>
#include <vector>
#include <queue>
#include <stack>
#include <utility>

using namespace std;

typedef long long signed int ll;

constexpr ll NIL = -20000000000;

int g[101][101],n,d[101],f[101];

int main() {
    cin >> n;
    for(int i = 0;i < n;i++) {
        int u,k,v;
        cin >> u >> k;
        for(int j = 0;j < k;j++) {
            cin >> v;
            g[u][v]++;
        }
    }
    stack<int> dfs;
    int time = 2;
    dfs.push(1);
    d[1] = 1;
    bool flag = true;
    while(flag) {
        while (!dfs.empty()) {
            int u = dfs.top();
            bool fl = false;
            for (int i = 1; i <= n; i++) {
                if (g[u][i] && d[i] == 0 && u != i) {
                    dfs.push(i);
                    d[i] = time++;
                    fl = true;
                    break;
                }
            }
            if (!fl) {
                dfs.pop();
                f[u] = time++;
            }
        }
        flag = false;
        for(int i =1;i <= n;i++) if(d[i] == 0){flag = true;dfs.push(i);d[i] = time++;}
    }
    for(int i = 1;i <=n;i++) {
        cout << i << " " << d[i] << " " << f[i] <<endl;
    }
}