Primorial Of a Number

Primorial Of a NumberCodewars

Approach

1. find primes

   1. if parameter less than 1 return 0

   2. set variable primes = [2], currentNum = 3

   3. trying each primes modulo calculate and if all modulo remainder not 0 that's prime. add to that prime to *primes* and move to next(n+1) number until find primes size same with input

2. factorial of process-1

Solution

JavaScript

const findPrimes = (primeCount) => {
  if (primeCount < 1) {
    return 0;
  }
  
  const primes = [2];
  
  let currentNum = 3;
  
  while (primes.length !== primeCount) {
    if (!primes.some((v) => currentNum % v === 0)) {
      primes.push(currentNum);
    }
    currentNum += 1;
  }
  
  return primes;
};

const numPrimorial = (n) => findPrimes(n).reduce((acc, cur) => acc * cur);