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
	for {
		startNode := findStartNode(childrenMap, timeRecordMap)
		if startNode > 0 {
			visit(startNode, &timer, childrenMap, timeRecordMap)
		} else {
			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
		}
	}
	if x < 0 {
		return -1
	}

	found := false
	i := 0
	for i < len(childrenMap) {
		children := childrenMap[i]
		for j := 0; j < len(children); j++ {
			if children[j] == x {
				x = j + 1
				found = true
				break
			}
		}
		if found {
			i = 0
		} else {
			i++
		}
	}
	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 <bits/stdc++.h>
#define LOOP(n) for (int _i = 0; _i < (n); _i++)
#define REP(i, n) for (int i = 0; i < (n); ++i)
#define RREP(i, n) for (int i = (n); i >= 0; --i)
#define FOR(i, r, n) for (int i = (r); i < (n); ++i)
#define ALL(obj) begin(obj), end(obj)
using namespace std;
using ll = long long;
using ull = unsigned long long;

const int INF = 2100100100;
const int MOD = 1e9 + 7;

// 多次元 vector 生成
template <class T>
vector<T> make_vec(size_t a) {
    return vector<T>(a);
}
template <class T, class... Ts>
auto make_vec(size_t a, Ts... ts) {
    return vector<decltype(make_vec<T>(ts...))>(a, make_vec<T>(ts...));
}
template <class T>
bool chmax(T &a, const T &b) {
    if (a < b) {
        a = b;
        return 1;
    }
    return 0;
}
template <class T>
bool chmin(T &a, const T &b) {
    if (b < a) {
        a = b;
        return 1;
    }
    return 0;
}

using Graph = vector<vector<int>>;

int N, M, K, Q;
int t;
int used[200];
void dfs(const Graph &G, vector<tuple<int, int, int>> &ans, int node) {
    t++;
    int d = t;
    used[node] = 1;
    for (auto v : G[node]) {
        if (used[v] == 0) {
            dfs(G, ans, v);
        }
    }
    t++;
    int f = t;
    ans.push_back(make_tuple(node, d, f));
}

int main() {
    // cin.tie(0);
    // ios::sync_with_stdio(false);

    cin >> N;
    Graph G(N);
    memset(used, 0, sizeof(used));
    REP(i, N) {
        int u, k;
        cin >> u >> k;
        u--;
        REP(j, k) {
            int v;
            cin >> v;
            v--;
            G[i].push_back(v);
        }
        sort(ALL(G[i]));
    }

    vector<tuple<int, int, int>> ans;
    t = 0;
    REP(u, N) {
        if (used[u] != 1) {
            dfs(G, ans, u);
        }
    }
    sort(ALL(ans));

    REP(i, (int)ans.size()) { cout << get<0>(ans[i]) + 1 << " " << get<1>(ans[i]) << " " << get<2>(ans[i]) << endl; }

    return 0;
}

C++: #include <bits/stdc++.h>
using namespace std;

#define debug(x) cout <<"DEBUG"<<" "<< #x << ":" << x << '\n'

// n回繰り返し
#define rep(i,n) for(int i = 0; i < ((int)(n)); i++)   // 0-indexed昇順
#define rep1(i,n) for(int i = 1; i <= ((int)(n)); i++) // 1-indexed昇順
#define rrep(i,n) for(int i = ((int)(n)-1); i >= 0; i--)  // 0-indexed降順
#define rrep1(i,n) for(int i = ((int)(n)); i >= 1; i--)   // 1-indexed降順
#define all(x) (x).begin(),(x).end()

typedef long long ll;
typedef long double ld;
typedef vector<int> vi;
typedef vector<vi> vii;  // 2次元配列
typedef vector<ll> vll;
typedef vector<double> vd;
typedef pair<int, int> PII;

template<typename T>
using vec = vector<T>;
template<class T>
using maxheap = std::priority_queue<T>;
template<class T>
using minheap = std::priority_queue<T, std::vector<T>, std::greater<T>>;

template<class T,class U> inline bool chmax(T &a, const U &b){if(a<b){a=b;return 1;}return 0;}
template<class T,class U> inline bool chmin(T &a, const U &b){if(a>b){a=b;return 1;}return 0;}

const ld Pi = std::acos(-1.0L);
const ll infll = (1LL<<62)-1;
const int inf = (1<<30)-1;
const int mod = 1000000007;
// const int mod = 998244353;

/*GRAPH_TEMPLATE=============================================*/
template<typename T>
class Edge {
public:
    int srch; //searched?探索状態記録「null = -1」
    int to; //辺の行き先
    T cost; //辺の重み
    Edge(int t, T w) : srch(-1), to(t), cost(w) {}
    Edge(int t, T w, int src) : srch(src), to(t), cost(w) {}
};
template<typename T>
using W_Graph = std::vector<std::vector<Edge<T>>>;   //重み付きグラフ
using Graph = std::vector<std::vector<int>>;         //通常グラフ
template<typename T>
using Matrix = std::vector<std::vector<T>>;          //隣接行列(使わなさそう...)


vi d,f;
Graph g;
int TIME;
/*FUNCs=================================================*/
void recursive(int u) {
    d[u] = ++TIME;
    for(auto &v : g[u]) {
        if(d[v] != 0) continue;
        recursive(v);
    }
    f[u] = ++TIME;
}

/*MAIN==================================================*/
signed main(){
    int _StartTime_ = clock();
    cin.tie(nullptr);
    ios::sync_with_stdio(false);   //cin cout 高速化
    // cout << fixed << setprecision(15);

    int n; cin >> n;
    d.resize(n+1), f.resize(n+1);
    g.resize(n+1);

    rep(i,n) {
        int u,v; cin >> u;
        u;
        g[0].push_back(u);
        int k; cin >> k;
        rep(j,k) {
            cin >> v;
            v;
            g[u].push_back(v);
        }
    }

    TIME = -1;
    recursive(0);

    for(int i = 1; i <= n; ++i) {
        cout << i << ' ';
        cout << d[i] << ' ';
        cout << f[i] << '\n';
    }

    // printf("ExcutionTime: %d /ms\n",1000*(int)((clock()-_StartTime_)/CLOCKS_PER_SEC));
}