Go: package main

import (
	"fmt"
)

func main() {
	var n int
	fmt.Scan(&n)
	g := make([][]int, n+1)
	for i := 0; i < n; i++ {
		var u,k int
		fmt.Scan(&u)
		fmt.Scan(&k)
		g[u] = make([]int, k)
		for j := 0; j < k; j++ {
			fmt.Scan(&g[u][j])
		}
	}

	d := make([]int, n+1)
	f := make([]int, n+1)
	t := 1
	for i := 1; i <= n; i++ {
		t = dfs(&g, &d, &f, i, t)
	}

	for i := 1; i <= n; i++ {
		fmt.Printf("%d %d %d\n", i, d[i], f[i])
	}
}

func dfs(g *[][]int, d *[]int, f *[]int, id int, t int) int {
	if (*d)[id] > 0 {
		return t
	}
	(*d)[id] = t
	t += 1
	for i := 0; i < len((*g)[id]); i++ {
		t = dfs(g, d, f, (*g)[id][i], t)
	}
	(*f)[id] = t
	return t+1
}

C++: /**
 * @brief  : c++ code for AtCoder
 * @author : rk222
 * @created: 2020.03.08 13:10:16
 */

#define _CRT_SECURE_NO_WARNINGS
#include <algorithm>
#include <bitset>
#include <cmath>
#include <cstdio>
#include <iostream>
#include <map>
#include <queue>
#include <set>
#include <stack>
#include <string>
#include <vector>
using namespace std;

// #define int long long

typedef long long ll;
typedef long double ld;
typedef pair<int, int> P;
typedef pair<int, P> P1;
typedef tuple<int, int, int> T;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<ll> vl;
typedef vector<P> vp;
typedef vector<tuple<int, int, int>> vt;

#define fr first
#define sc second
#define mp make_pair
#define pb push_back
#define rep(i, x) for (int i = 0; i < x; i++)
#define rep1(i, x) for (int i = 1; i <= x; i++)
#define srep(i, s, x) for (int i = s; i < x; i++)
#define rrep(i, x) for (int i = x - 1; i >= 0; i--)
#define rrep1(i, x) for (int i = x; i > 0; i--)
#define rsrep(i, s, x) for (int i = x - 1; i >= s; i--)
#define maxs(x, y) (x = max(x, y))
#define mins(x, y) (x = min(x, y))
#define limit(x, l, r) max(l, min(x, r))
#define lims(x, l, r) (x = max(l, min(x, r)))
#define sor(v) sort(v.begin(), v.end())
#define rev(s) reverse(s.begin(), s.end())
#define lb(vec, a) lower_bound(vec.begin(), vec.end(), a)
#define ub(vec, a) upper_bound(vec.begin(), vec.end(), a)
#define uniq(vec) vec.erase(unique(vec.begin(), vec.end()), vec.end())
#define mp1(a, b, c) P1(a, P(b, c))
#define dame                                                                                  \
    puts("-1");                                                                               \
    return 0
#define yn                                                                                    \
    puts("Yes");                                                                              \
    else puts("No")
#define YN                                                                                    \
    puts("YES");                                                                              \
    else puts("NO")

template <typename A, typename B> string to_string(pair<A, B> p);
template <typename A, typename B, typename C> string to_string(tuple<A, B, C> p);
template <typename A, typename B, typename C, typename D>
string to_string(tuple<A, B, C, D> p);
string to_string(const string &s) {
    return '"' + s + '"';
}
string to_string(const char *s) {
    return to_string((string)s);
}
string to_string(bool b) {
    return (b ? "true" : "false");
}
string to_string(vector<bool> v) {
    bool first = true;
    string ret = "{";
    for (int i = 0; i < static_cast<int>(v.size()); i++) {
        if (!first) {
            ret += ", ";
        }
        first = false;
        ret += to_string(v[i]);
    }
    ret += "}";
    return ret;
}
template <size_t N> string to_string(bitset<N> v) {
    string ret = "";
    for (size_t i = 0; i < N; i++) {
        ret += static_cast<char>('0' + v[i]);
    }
    return ret;
}
template <typename A> string to_string(A v) {
    bool first = true;
    string ret = "{";
    for (const auto &x : v) {
        string s = to_string(x);
        if (!first) {
            ret += ", ";
        }
        if (s[0] == '{') {
            s = "\n" + s;
        }
        first = false;
        ret += s;
    }
    if (ret[ret.size() - 1] == '}') {
        ret += "\n}";
    } else {
        ret += "}";
    }
    return ret;
}
template <typename A, typename... Lest> string to_string(A *v, int n, Lest... L) {
    bool first = true;
    string ret = "{";
    rep(i, n) {
        auto x = v[i];
        string s = to_string(x, L...);
        if (!first) {
            ret += ", ";
        }
        if (s[0] == '{') {
            s = "\n" + s;
        }
        first = false;
        ret += s;
    }
    if (ret[ret.size() - 1] == '}') {
        ret += "\n}";
    } else {
        ret += "}";
    }
    return ret;
}
template <typename A, typename B> string to_string(pair<A, B> p) {
    return "(" + to_string(p.first) + ", " + to_string(p.second) + ")";
}
template <typename A, typename B, typename C> string to_string(tuple<A, B, C> p) {
    return "(" + to_string(get<0>(p)) + ", " + to_string(get<1>(p)) + ", " +
           to_string(get<2>(p)) + ")";
}
template <typename A, typename B, typename C, typename D>
string to_string(tuple<A, B, C, D> p) {
    return "(" + to_string(get<0>(p)) + ", " + to_string(get<1>(p)) + ", " +
           to_string(get<2>(p)) + ", " + to_string(get<3>(p)) + ")";
}
void name_disp(string s) {
    cerr << "-------" << endl;
    cerr << s << ": " << endl;
}
void val_disp() {
    cerr << endl;
}
template <typename First, typename... Lest> void val_disp(First F, Lest... L) {
    cerr << to_string(F) << endl;
    val_disp(L...);
}
template <typename A, typename... Lest> void val_disp(A *v, Lest... L) {
    cerr << to_string(v, L...) << endl;
    val_disp();
}
#define disp(...)                                                                             \
    name_disp(#__VA_ARGS__);                                                                  \
    val_disp(__VA_ARGS__)
#define adisp(a, ...)                                                                         \
    name_disp(#a);                                                                            \
    val_disp(a, __VA_ARGS__)

#ifdef int
const ll INF = 1002003004005006007ll;
#else
const int INF = 1002003004;
#endif

const int M = 100000000;
const int dir_4[4][2] = {{1, 0}, {0, 1}, {-1, 0}, {0, -1}};
const int dir_8[8][2] = {{1, 0}, {1, 1}, {0, 1}, {-1, 1}, {-1, 0}, {-1, -1}, {0, -1}, {1, -1}};

/* ------------------------------------- */

struct edge {
    int to;
    int cost;
};

vector<int> G[110];

int d[110], f[110];

int dfs(int from, int time) {
    if (d[from] < INF) {
        return time;
    }

    d[from] = min(d[from], time);
    time++;
    rep(i, G[from].size()) {
        time = dfs(G[from][i], time);
    }
    f[from] = min(f[from], time);
    return time + 1;
}

signed main() {
    int n;
    scanf("%d", &n);
    rep(i, n) {
        int u, k;
        scanf("%d%d", &u, &k);
        u--;
        rep(i, k) {
            int v;
            scanf("%d", &v);
            v--;
            G[u].pb(v);
        }
        sor(G[u]);
    }

    rep(i, n) {
        d[i] = INF;
        f[i] = INF;
    }
    int time = 1;
    rep(i, n) {
        time = dfs(i, time);
    }

    rep(i, n) {
        printf("%d %d %d\n", i + 1, d[i], f[i]);
    }

    /* --------------------------------- */
    return 0;
};

C++: #include <iostream>
using namespace std;
int d[101] = {},f[101];
int a[101][101];
int kosu[101];
int joutai = 0;
void dfs(int x){
	joutai++;
	d[x] = joutai;
	for(int i = 1;i <= kosu[x];i++){
		if(d[a[x][i]] == 0){
			dfs(a[x][i]);
		}
	}
	joutai++;
	f[x] = joutai;
}

int main(){
	int n,x;
	cin >> n;
	for(int i = 0;i < n;i++){
		cin >> x;
		cin >> kosu[x];
		for(int j = 1;j <= kosu[x];j++){
			cin >> a[x][j];
		}
	}
	for(int i = 1;i <= n;i++){
		if(d[i] == 0){
			dfs(i);	
		}	
	}

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