JavaScript/Maths/CoPrimeCheck.js

/*
    Problem statement and Explanation : https://en.wikipedia.org/wiki/Coprime_integers

    In number theory, two integers a and b are coprime, relatively prime or
    mutually prime if the only positive integer that is a divisor of both
    of them is Consequently, any prime number that divides one of a
    or b does not divide the other. This is equivalent to their greatest
    common divisor (gcd) being. One says also a is prime to b or a
    is coprime with b.
*/

// Here we use a GetEuclidGCD method as a utility.
const GetEuclidGCD = (arg1, arg2) => {
  let less = arg1 > arg2 ? arg2 : arg1
  for (less; less >= 2; less--) {
    if (arg1 % less === 0 && arg2 % less === 0) return less
  }
  return less
}

// CoPrimeCheck function return the boolean in respect of the given number is co-prime or not.
/**
 * CoPrimeCheck function return the boolean in respect of the given number is co-prime or not.
 * @param {Number} firstNumber first number for checking is prime or not.
 * @param {Number} secondNumber second number for checking is prime or not.
 * @returns return correspond boolean value, if both number are co-prime return `true`, else return `false`.
 */
const CoPrimeCheck = (firstNumber, secondNumber) => {
  // firstly, check that input is a number or not.
  if (typeof firstNumber !== 'number' || typeof secondNumber !== 'number') {
    return new TypeError('Argument is not a number.')
  }
  /*
    This is the most efficient algorithm for checking co-primes
    if the GCD of both the numbers is 1 that means they are co-primes.
    */
  return GetEuclidGCD(firstNumber, secondNumber) === 1
}

export { CoPrimeCheck }