testing1/collatz.scala
author Christian Urban <urbanc@in.tum.de>
Wed, 07 Nov 2018 12:08:01 +0000
changeset 198 c2d36d8ee2a7
parent 197 ff7f68a511a6
child 199 2e13dedd922e
permissions -rw-r--r--
updated handout

// Part 1 about the 3n+1 conjecture
//==================================
package CW6a 


object CW6a {

def collatz(n: Long): Long =
  if (n == 1) 1 else
    if (n % 2 == 0) 1 + collatz(n / 2) else 
      1 + collatz(3 * n + 1)


def collatz_max(bnd: Long): (Long, Long) = {
  val all = for (i <- (1 to bnd.toInt).toList) yield collatz(i)
  val max = all.max
  (max, all.indexOf(max) + 1)
}


}



(1 to 10).map(collatz(_))