const rl = require("readline").createInterface({ input: process.stdin });
var iter = rl[Symbol.asyncIterator]();
const readline = async () => (await iter.next()).value;
void (async function () {
// Write your code here
let params = [];
while ((line = await readline())) {
let tokens = line.split(" ");
// let a = parseInt(tokens[0]);
// let b = parseInt(tokens[1]);
// console.log(a + b);
params.push(tokens);
}
// console.log(params[0][0])
let str = params[0][0];
// console.log(str)
let count = 0;
let bool = true;
for (let i = 0; i < str.length; i++) {
if (str[i] === "a") {
count++;
} else if (str[i] === "b") {
if (count > 0) {
count--;
} else {
console.log("Bad");
bool = false;
break;
}
}
}
if (count === 0&&bool) {
console.log("Good");
} else {
if (bool) console.log("Bad");
}
})();