SAP Community Coding Challenge Nr.2

HTML

<!DOCTYPE html>
<html>
<head>
</head>
<body>
  <div id="div1">
    <h>||SAP Community Coding Challenge Nr.2||</h>
  </div>
 
</body>
</html>

JavaScript

const memoize = (fn) => {
  let cache = {};
	return (...args) => {
		let n = args[0];
		if (n in cache) {
			return cache[n];
		}
		else {
			let result = fn(n);
			cache[n] = result;
			return result;
		}
	}
}

const collatz = memoize((n) => n === 1 ? 1 : 1 + collatz( n % 2 === 0 ? n / 2 : 3 * n + 1 ));

var longest_collatz = 0; output = 0;
let start = (new Date()).getTime()

for (var x = 1; x < 1000000; x++){
    var x_longest_collats = collatz(x);
    if (longest_collatz < x_longest_collats){
	 		longest_collatz = x_longest_collats 
	 	  output = x;
	  }
}
let end = (new Date()).getTime()
let performance = end - start;

// Output
var contCollatz = document.createTextNode("Longest Collatz Sequence: " + output + " - Processing Time: " + performance + " ms" ); 
document.body.appendChild(contCollatz)