function printHeap(heap, index, level) {
    if (index >= heap.length) {
        return;
    }
    console.log("  ".repeat(level) + heap[index]);
    printHeap(heap, 2 * index + 1, level + 1);
    printHeap(heap, 2 * index + 2, level + 1);
}

//You can call this function by passing in the heap array and the index of the root node, which is typically 0, and level = 0.

let heap = [3, 8, 7, 15, 17, 30, 35, 2, 4, 5, 9];
printHeap(heap,0,0)

const head = arr => (arr && arr.length ? arr[0] : undefined);

head([1, 2, 3]); // 1
head([]); // undefined
head(null); // undefined
head(undefined); // undefined

class SequentialQueue{	//if you want it to go backwards, too bad
	next(){
		return this.i++;
	}
	constructor(start = 0){
		this.i = start;
	}
}
const que = new SequentialQueue(0);
for(let i = 0; i < 10; i++){
	console.log(que.next());
}

const jwt = require("jsonwebtoken");

const authToken = (req, res, next) => {
	const token = req.headers["x-auth-token"];

	try {
	req.user = jwt.verify(token, process.env.ACCESS_TOKEN_SECRET);

	next();
	} catch (err) {
	console.log(err.message);
	res.status(401).json({ msg: "Error authenticating token" });
	}
};

module.exports = authToken;

const ResponsiveCardImg = styled(Card.Img)`
    // For screens wider than 768px
    @media(min-width: 768px) {
        // Your responsive styles here.
    }

    // For screens smaller than 768px
    @media(max-width: 768px) {
        // Your responsive styles here.
    }
`

export default function App() {
    return (
        <MainContainer>
            <Container>
                <Card text='white' bg='dark' style={styles.mainCard}>
                <ResponsiveCardImg
                    style={styles.cardImage}
                    onClick={handleClick}
                    src={apeImage}
                    alt='Degenerate Ape Academy'
                />
                <Card.Body>
                    <Card.Title className='text-center' as='h2'>
                    {apeId}
                    </Card.Title>
                </Card.Body>
                </Card>
            </Container>
        </MainContainer>
    );
}

questions = Array.from(document.querySelectorAll(".multiple-choice-question"));
async function hackRadio(question){
	if(question.querySelector(".question-chevron").getAttribute("aria-label") == "Question completed") return;
	let answerChoices = question.querySelectorAll(".zb-radio-button");
	async function guess(answerChoice){
		answerChoice.querySelector("label").click();
	}
	let pause = 0;
	for(let answerChoice of answerChoices){
		setTimeout(()=>{guess(answerChoice)},pause);	//No need to check given that it will record the correct answer anyways.
		pause += 1000;
	}
}
for(let question of questions){
	hackRadio(question);
}
questions = Array.from(document.querySelectorAll(".short-answer-question"));
async function hackShortAnswer(question){
	if(question.querySelector(".question-chevron").getAttribute("aria-label") == "Question completed") return;
	question.querySelector("textarea").value = question.querySelector(".forfeit-answer").textContent;
	//question.querySelector(".check-button").click(); They are smart bastards
}
for(let question of questions){
	const showAnswerButton = question.querySelector(".show-answer-button");
	showAnswerButton.click();
	showAnswerButton.click();
	hackShortAnswer(question);
}