JSFiddle - React, Tailwind, and code Playground

by Giorgio Malvone

HTML

<input type="button" value="Factorialise" onclick="FirstFactorial(prompt('Enter a number:'))"></input>

JavaScript

function FirstFactorial(num) { 

  var res = 1;
  for (var i = 2; i <= num; i++) {
    res *= i;
  }
  alert(res);            
}