Problem:
Score : 100 points

Problem Statement

The door of Snuke's laboratory is locked with a security code.

The security code is a 4-digit number. We say the security code is hard to enter when it contains two consecutive digits that are the same.

You are given the current security code S. If S is hard to enter, print Bad; otherwise, print Good.

Constraints

S is a 4-character string consisting of digits.

Input

Input is given from Standard Input in the following format:

S

Output

If S is hard to enter, print Bad; otherwise, print Good.

Sample Input 1

3776

Sample Output 1

Bad

The second and third digits are the same, so 3776 is hard to enter.

Sample Input 2

8080

Sample Output 2

Good

There are no two consecutive digits that are the same, so 8080 is not hard to enter.

Sample Input 3

1333

Sample Output 3

Bad

Sample Input 4

0024

Sample Output 4

Bad

Solution in C++14 (GCC 5.4.1) (judge verdict: Accepted)

#include <iostream>
#include <fstream>
#include <cstdio>
#include <cstring>
#include <cmath>
#include <algorithm>
#include <vector>
#include <string>
#include <queue>
#include <deque>
#include <stack>
#include <set>
#include <map>
#include <bitset>
#include <sstream>
#include <iomanip>

using namespace std;

typedef long long ll;
typedef vector <int> vi;
typedef vector <vector <int>> vii;
typedef vector <long long> vll;
typedef vector <string> vs;
typedef vector <char> vc;
typedef set <int> si;
typedef set <string> ss;
typedef queue <int> qi;
typedef queue <long long> qll;
typedef queue <string> qs;
typedef queue <char> qc;
typedef struct board board;
typedef pair <int, int> pi;
typedef pair <long long, long long> pll;
typedef pair <int, pair<int, int>> pii;

#define eb emplace_back
#define ppb pop_back
#define clr(a) a.clear()
#define F first
#define S second
#define mkp make_pair

#define sz(x) (int)(x).size()
#define all(x) (x).begin(), (x).end()

#define left(x) x * 2
#define right(x) x * 2 + 1

#define meme(a, b, c) fill(a + 1, a + 1 + b, c)

#define max(a, b) (a > b ? a : b)
#define min(a, b) (a > b ? b : a)
#define abs(a) (a > 0? a : -(a))

#define move(s) s += "#"

#define fr(i, a, b) for (ll i = a; i <= b; ++ i)
#define rf(i, a, b) for (ll i = a; i >= b; -- i)

#define eprintf(...) fprintf(stderr, __VA_ARGS__);

void to_pray() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    cerr << "Ready\n";
}

const int N = 4e6 + 10;
const int NN = 1e3 + 10;
const int NNN = 2e3 + 9;
const int MOD = 1e9 + 7;
const int INF = 1e9 + 7;
const ll LLINF = 1e12 + 7;
const ll P = 53;
const int EPS = 1e-9 - 8;
const int vN = 2e4 + 10;
const int sz = (1 << 22) - 1;
const double PI = acos(-1);

int main () {
    to_pray();

    string s;
    cin >> s;
    
    for (int i = 0; i < sz(s) - 1; ++ i)
    	if (s[i] == s[i + 1])
    		return cout << "Bad", 0;
    
    cout << "Good";
    
    cout << '\n';
    return 0;
}