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)
	dfs(&g, &d, &f, 1, 1)

	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++: #include <bits/stdc++.h>
using namespace std;
#define N 100
int t = 0;
stack<int> st;
int d[N + 1], f[N + 1], V[N + 1];
int adj[N + 1][N + 1];

void dfs(int i, int n)
{
    for (int j = 0; j < V[i]; j++)
    {
        if (d[adj[i][j]] == -1)
        {
            d[adj[i][j]] = ++t;
            dfs(adj[i][j], n);
        }
    }
    f[i] = ++t;
}

int main()
{
    int n;
    cin >> n;
    V[0] = n;
    for (int i = 0; i < n; i++)
        adj[0][i] = i + 1;
    for (int i = 0; i < n; i++)
    {
        int u, k;
        cin >> u >> k;
        V[u] = k;
        for (int j = 0; j < k; j++)
        {
            int v;
            cin >> v;
            adj[u][j] = v;
        }
    }

    for (int i = 0; i <= n; i++)
        d[i] = f[i] = -1;

    dfs(0, n);

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

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{
            for(int i=0;i<num;i++){
                if(matrix[cur][i]==1){
                    if(dst[cur] +1 <= dst[i]){
                        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();
}

C++: #include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const ll MOD = 1e9 + 7;
const int inf = 1e9;
const ll INF = 1e18;
const double pi = 3.14159265358979323846;
#define rep(i, n) for (int i = 0; i < n; i++)
using Graph = vector<vector<int>>;
using pint = pair<int, int>;
int dx[4] = { 1, 0, -1, 0 }, dy[4] = { 0, 1, 0, -1 };

int n;
vector<int> first, last;
bool seen[100] = {};

void dfs (const Graph& g, int u, int& ptr) {
    first[u] = ptr++;
    seen[u] = 1;
    for (auto next : g[u]) {
        if (seen[next]) continue;
        dfs (g, next, ptr);
    }
    last[u] = ptr++;
}

int main() {
    cin >> n;
    Graph g (n);
    first.resize (n);
    last.resize (n);
    rep (i, n) {
        int a, k;
        cin >> a >> k;
        rep (j, k) {
            int b;
            cin >> b;
            g[a - 1].push_back (b - 1);
            //g[b].push_back (a);
        }
    }
    int ptr = 0;
    rep (i, n) {
        if (first[i] == 0 && last[i] == 0) {
            dfs (g, i, ptr);
        }
    }

    rep (i, n) cout << i + 1 << " " << first[i] + 1 << " " << last[i] + 1 << "\n";
}

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

#define REP(i,n) for(int i=0;i<n;++i)

const int MAX_N = 100;
int n, t = 0, flag[MAX_N] = {0}, d[MAX_N], f[MAX_N], G[MAX_N][MAX_N] = {0};

void dfs(int u) {
  int v;
  flag[u] = 1;
  d[u] = ++t;
  REP(v, n) {
    if (!G[u][v]) continue;
    if (!flag[v]) dfs(v);
  }
  flag[u] = 2;
  f[u] = ++t;
}

int main() {
  int u, v, k;
  cin >> n;
  REP(i, n) {
    cin >> u >> k;
    REP(j, k) {
      cin >> v;
      G[u - 1][v - 1] = 1;
    }
  }
  REP(i, n) if (!flag[i]) dfs(i);
  REP(i, n) cout << i + 1 << ' ' << d[i] << ' ' << f[i] << endl;
  return 0;
}

C++: /*
#include<iostream>
#include<stack>
using namespace std;

struct time_check {
    int find_time, end_time;
};

int main() {
    int G[101][101] = {0};
    time_check t[101];

    for (int i = 1; i <= 100; i++) t[i].end_time = 0;

    stack<int> S;
    int n, u, v, k, elapsed=1;
    cin >> n;
    for (int i = 0; i < n; i++) {
        cin >> u >> k;
        for (int j = 0; j < k; j++) {
            cin >> v;
            G[u][v] = 1;
        }
    }
    S.push(1);
    t[1].find_time = 1;
    while (! S.empty()) {
        elapsed++;
        u = S.top();
        for (int i = 1; i <= n + 1; i++) {
            if (G[u][i] == 1 && t[i].end_time == 0) {
                t[i].find_time = elapsed;
                G[u][i] = 0;
                S.push(i);
                break;
            }
            if (i == n + 1) {
                t[u].end_time = elapsed;
                S.pop();
            }
        }
    }

    for (int i = 1; i <= n; i++) {
        cout << i << " " << t[i].find_time << " " << t[i].end_time << endl;
    }

    return 0;
}
このコードはWrong Answerです...
理由は以下のコードのl.111のとこのように未訪問の頂点を始点としてdfsしてないから
*/

#include<iostream>
#include<stack>
using namespace std;
static const int N = 100;
static const int WHITE = 0;
static const int GRAY = 1;
static const int BRACK = 2;

int n, M[N][N];
int color[N], d[N], f[N], tt;
int nt[N];

// uに隣接するvを番号順に取得
int next(int u) {
    for (int v = nt[u]; v < n; v++) {
        nt[u] = v + 1;
        if (M[u][v]) return v;
    }
    return -1;
}

// スタックを用いた深さ優先探索
void dfs_visit(int r) {
    for (int i = 0; i < n; i++) nt[i] = 0;

    stack<int> S;
    S.push(r);
    color[r] = GRAY;
    d[r] = ++tt;

    while (! S.empty()) {
        int u = S.top();
        int v = next(u);
        if (v != -1) {
            if (color[v] == WHITE) {
                color[v] = GRAY;
                d[v] = ++tt;
                S.push(v);
            }
        } else {
            S.pop();
            color[u] = BRACK;
            f[u] = ++tt;
        }
    }
}

void dfs() {
    // 初期化
    for (int i = 0; i < n; i++) {
        color[i] = WHITE;
        nt[i] = 0;
    }
    tt = 0;

    // 未訪問のuを始点として深さ優先探索
    for (int u = 0; u < n; u++) {
        if (color[u] == WHITE) dfs_visit(u);
    }
    for (int i = 0; i < n; i++) {
        cout << i+1 << " " << d[i] << " " << f[i] << endl;
    }
}

int main() {
    int u, k, v;

    cin >> n;
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < n; j++) M[i][j] = 0;
    }

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

    dfs();

    return 0;
}

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

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

int step;
void dfs(int start){
	stack<int> S;
	S.push(start);

	++step;
	d[start]=step;

	while(S.size()){
		int u=S.top();

		int v=0;
		for(int i=1;i<=n;i++){
			if(adj[u][i]==1 && d[i]==0){
				v=i;	break;
			}
		}

		++step;
		if(v==0){
			f[u]=step;
			S.pop();
		}else{
			d[v]=step;
			S.push(v);
		}
	}
}

int main(){
	cin>>n;
	for(int i=0;i<n;i++){
		int u,k;	cin>>u>>k;
		for(int j=0;j<k;j++){
			int v;	cin>>v;
			adj[u][v]=1;
		}
	}

	step=0;
	for(int i=1;i<=n;i++){
		if(d[i]==0)dfs(i);
	}

	for(int i=1;i<=n;i++){
		printf("%d %d %d\n",i,d[i],f[i]);
	}

	return 0;
}