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 JavaScript (node.js v5.12) (judge verdict: Runtime Error)

function main(input) {
    let prevNum = input[0];
    for (let digit = 1; digit < 4; digit++) {
        if (input[digit] === prevNum) {
            console.log("Bad");
            break;
        }
        if (digit === 3) {
            console.log("Good");
        }
        prevNum = input[digit];
    }
}
main(require('fs').readFileSync('/dev/stdin', 'utf8'));