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 Ruby (2.3.3) (judge verdict: Runtime Error)

#include <iostream>
#include <vector>
#include <string>
#include <tuple>
#include <algorithm>
#include <numeric>
#include <climits>
#include <map>
#include <functional>
#include <cmath>
#include <cassert>
#include <set>

using namespace std;

template<typename T>inline T get(){T x;cin>>x;return x;}

int main()
{
    char prev = '?';
    const char* ans = "Good";

    for (int i = 0; i < 4; i++) {
        char c;

        cin >> c;
        if (c == prev)
            ans = "Bad";
        prev = c;
    }
    cout << ans << endl;
    return 0;
}