Have the function FirstFactorial(num) take the num parameter being passed and return the factorial of it. For example: if num = 4, then your program should return (4 * 3 * 2 * 1) = 24. For the test cases, the range will be between 1 and 18 and the input will always be an integer.

https://coderbyte.com/editor/First%20Factorial:JavaScript?utm_campaign=NewHomepage

function FirstFactorial(num) { 

  // code goes here 
  let result = 1;
    for (let i = num; i >= 1; i--) {
        result *= i;
    }

  return result ; 

}
   
// keep this function call here 
console.log(FirstFactorial(readline()));