diff -r e9d14d58be3c -r daf561a83ba6 pre_marking1/collatz.scala
--- a/pre_marking1/collatz.scala	Thu Jan 13 12:55:03 2022 +0000
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,50 +0,0 @@
-// Basic Part about the 3n+1 conjecture
-//==================================
-
-// generate jar with
-//   > scala -d collatz.jar  collatz.scala
-
-object CW6a { // for purposes of generating a jar
-
-def collatz(n: Long): Long =
-  if (n == 1) 0 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 <- (1L to bnd)) yield (collatz(i), i)
-  all.maxBy(_._1)
-}
-
-//collatz_max(1000000)
-//collatz_max(10000000)
-//collatz_max(100000000)
-
-/* some test cases
-val bnds = List(10, 100, 1000, 10000, 100000, 1000000)
-
-for (bnd <- bnds) {
-  val (steps, max) = collatz_max(bnd)
-  println(s"In the range of 1 - ${bnd} the number ${max} needs the maximum steps of ${steps}")
-}
-
-*/
-
-def is_pow(n: Long) : Boolean = (n & (n - 1)) == 0
-
-def is_hard(n: Long) : Boolean = is_pow(3 * n + 1)
-
-def last_odd(n: Long) : Long = 
-  if (is_hard(n)) n else
-    if (n % 2 == 0) last_odd(n / 2) else 
-      last_odd(3 * n + 1)
-
-
-//for (i <- 130 to 10000) println(s"$i: ${last_odd(i)}")
-//for (i <- 1 to 100) println(s"$i: ${collatz(i)}")
-
-}
-
-
-