const luhnCheck = num => {
  let arr = (num + '')
    .split('')
    .reverse()
    .map(x => parseInt(x));
  let lastDigit = arr.splice(0, 1)[0];
  let sum = arr.reduce(
    (acc, val, i) => (i % 2 !== 0 ? acc + val : acc + ((val *= 2) > 9 ? val - 9 : val)),
    0
  );
  sum += lastDigit;
  return sum % 10 === 0;
};

luhnCheck('4485275742308327'); // true
luhnCheck(6011329933655299); //  true
luhnCheck(123456789); // false

const reverse = str => str.split('').reverse().join('');
reverse('hello world');     
// Result: 'dlrow olleh'

//Use at https://mee6.xyz/leaderboard/732262089447702588
//Higher the spammy stat, the more spammy that person is.
//This is because mee doesn't give experience to people who post more comments in a minute.
function statBlock(title, value){
	let elm = document.createElement("div");
	elm.className = "leaderboardPlayerStatBlock";
	let titleElm = document.createElement("div");
	titleElm.className = "leaderboardPlayerStatName";
	titleElm.textContent = title;
	let valueElm = document.createElement("div");
	valueElm.className = "leaderboardPlayerStatValue";
	valueElm.textContent = value;
	elm.appendChild(titleElm);
	elm.appendChild(valueElm);
	elm.remove = function(){
	this.parentElement.removeChild(this);
	}
	return elm;
}
for(let player of Array.from(document.getElementsByClassName("leaderboardPlayer"))){
	if(player.spamminess) player.spamminess.remove();
	let messages = null;
	let experience = null;
	const statBlockArray = Array.from(player.querySelectorAll(".leaderboardPlayerStatBlock"));
	for(let statBlock of statBlockArray){
	const statName = statBlock.querySelector(".leaderboardPlayerStatName").textContent;
	const text = statBlock.querySelector(".leaderboardPlayerStatValue").textContent;
	const number = ((text.includes("k"))? (text.replace("k","") * 1000.0) : +(text));
	if(statName.includes("MESSAGES")){
	messages = number;
	}else if(statName.includes("EXPERIENCE")){
	experience = number;
	}
	}
	const stats = player.querySelector(".leaderboardPlayerStats");
	const messagesElement = stats.firstChild;

	const spamminess = ((messages/experience)*2000.0).toFixed(2);
	
	player.spamminess = stats.insertBefore(statBlock("SPAMMINESS", spamminess), messagesElement);
}

# Acronyms

## Computer Numerical Control (CNC)

- Typicalldfdfsdffdafdasgfdgfgfdfdafdasfdafda

arr = [] // empty array
const isEmpty = arr => !Array.isArray(arr) || arr.length === 0;

// Examples
isEmpty([]); // true
isEmpty([1, 2, 3]); // false

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)