// Part 1 about the 3n+1 conjecture+
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//==================================+
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+
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object CW6a {+
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+
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def collatz(n: Long): Long =+
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  if (n == 1) 1 else+
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    if (n % 2 == 0) 1 + collatz(n / 2) else +
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      1 + collatz(3 * n + 1)+
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+
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+
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def collatz_max(bnd: Long): (Long, Long) = {+
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  val all = for (i <- (1 to bnd.toInt).toList) yield collatz(i)+
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  val max = all.max+
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  (max, all.indexOf(max) + 1)+
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}+
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+
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+
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// some testing harness...5 Mio pushes the envelope+
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+
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val bnds = List(2, 10, 100, 1000, 10000, 100000, +
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		77000, 90000, 1000000, 5000000)+
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+
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for (bnd <- bnds) {+
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  val (steps, max) = collatz_max(bnd)+
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  println(s"In the range of 1 - ${bnd} the number ${max} needs the maximum steps of ${steps}")+
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}+
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+
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+
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}+
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