First Factorial

first-factorial.markdown

First Factorial

A Pen by Jeff on CodePen.

License.

index.html

<script src='https://scottdalessandro.github.io/jasmine-total/js/jasmine-suite.min.js'></script>

script.js

/*
Factorial

Create the function **factorial(num)** that returns the factorial of the parameter.

Not sure what a factorial is? Check [this link](http://www.rapidtables.com/math/algebra/Factorial.htm) for a refresher!

<br> 

####Example:

- INPUT: factorial(4);
- OUTPUT: 24

-INPUT: factorial(5);
-OUTPUT: 120

<br>
<hr>
<br>


*/

// Write Code Below
function factorial(num){
  var total = 1;
  for (num; num > 1; num--){
   total *= num;
  }
  return total;

}
  



























































































































describe('factorial', function(){
	it('factorial is a function', function(){
		expect(typeof factorial).toEqual('function');
	});

	it('factorial returns a number value', function(){
		expect(typeof factorial(5)).toEqual('number');
	});

	it('returns the factorial of the number argument', function(){
		expect(factorial(5)).toEqual(120);
		expect(factorial(7)).toEqual(5040);
		expect(factorial(10)).toEqual(3628800);
	});

});