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     1  | 
// Part 1 about the 3n+1 conjecture
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     2  | 
//==================================
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     3  | 
package CW6a 
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     4  | 
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     5  | 
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     6  | 
object CW6a {
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     7  | 
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     8  | 
def collatz(n: Long): Long =
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     9  | 
  if (n == 1) 1 else
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    10  | 
    if (n % 2 == 0) 1 + collatz(n / 2) else 
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    11  | 
      1 + collatz(3 * n + 1)
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    12  | 
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    13  | 
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    14  | 
def collatz_max(bnd: Long): (Long, Long) = {
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    15  | 
  val all = for (i <- (1 to bnd.toInt).toList) yield collatz(i)
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    16  | 
  val max = all.max
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    17  | 
  (max, all.indexOf(max) + 1)
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    18  | 
}
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    19  | 
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    20  | 
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    21  | 
}
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    22  | 
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    23  | 
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    24  | 
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    25  | 
(1 to 10).map(collatz(_))
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