题解 | 好串

const rl = require("readline").createInterface({ input: process.stdin });
var iter = rl[Symbol.asyncIterator]();
const readline = async () => (await iter.next()).value;
// 使用类似堆栈的方式处理，使用计数以减少时间复杂度
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;
    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");
                return;
            }
        }
    }
    if (count === 0) {
        console.log("Good");
    } else {
         console.log("Bad");
    }
})();