Algorithm // Finding Prime Factors for a number // Inefficient

prime-factors.ts

function isPrime(num: number): boolean {
  return findFactors(num).length === 2;
}

function findFactors(num1: number): Array<number> {
  let factors: Array<number> = [];

  for (let index = 0; index <= num1; index++) {
    if (num1 % index == 0) {
      factors.push(index);
    }
  }
  return factors;
}

function findPrimeFactors(num1: number): Array<number> {
  let factors: Array<number> = [];
  const primes = getPrimes(num1);

  for (let index = 0; index <= primes.length; index++) {
    const primeNumber = primes[index];
    if (num1 % primeNumber == 0) {
      factors.push(primeNumber);
    }
  }
  return factors;
}

function getPrimes(num: number): Array<number> {
  let primes: Array<number> = [];
  for (let index = 0; index <= num; index++) {
    if (isPrime(index)) {
      primes.push(index);
    }
  }
  return primes;
}

console.log("Prime Factors =", findPrimeFactors(15));