Source code in the scala programming language

@tailrec
def gcd(a: Int, b: Int): Int = if(b == 0) a else gcd(b, a%b)
def totientLaz(num: Int): Int = LazyList.range(2, num).count(gcd(num, _) == 1) + 1


def totientPrd(num: Int): Int = {
  @tailrec
  def dTrec(f: Int, n: Int): Int = if(n%f == 0) dTrec(f, n/f) else n
  
  @tailrec
  def tTrec(ac: Int, i: Int, n: Int): Int = if(n != 1){
    if(n%i == 0) tTrec(ac*(i - 1)/i, i + 1, dTrec(i, n))
    else tTrec(ac, i + 1, n)
  }else{
    ac
  }
  
  tTrec(num, 2, num)
}


@tailrec
def scrub(f: Long, num: Long): Long = if(num%f == 0) scrub(f, num/f) else num
def totientLazPrd(num: Long): Long = LazyList.iterate((num, 2: Long, num)){case (ac, i, n) => if(n%i == 0) (ac*(i - 1)/i, i + 1, scrub(i, n)) else (ac, i + 1, n)}.find(_._3 == 1).get._1