| author | Christian Urban <urbanc@in.tum.de> |
| Tue, 22 Jan 2019 12:53:05 +0000 | |
| changeset 258 | ebe71908b13e |
| parent 11 | 417869f65585 |
| permissions | -rw-r--r-- |
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48a477fdef21
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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import scala.annotation.tailrec |
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48a477fdef21
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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def collatz(n: Long): List[Long] = |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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if (n == 1) List(1) else |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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if (n % 2 == 0) (n::collatz(n / 2)) else |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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(n::collatz(3 * n + 1)) |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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def collatz1(n: Long): Int = |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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if (n == 1) 1 else |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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if (n % 2 == 0) (1 + collatz1(n / 2)) else |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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(1 + collatz1(3 * n + 1)) |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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@tailrec |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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def collatz2(n: Long, acc: Int): Int = |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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if (n == 1) acc else |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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if (n % 2 == 0) collatz2(n / 2, acc + 1) else |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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collatz2(3 * n + 1, acc + 1) |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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collatz(1) |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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collatz(2) |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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collatz(3) |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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collatz(4) |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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collatz(5) |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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collatz(6).length |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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collatz(7) |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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collatz(8) |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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collatz(9).length |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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collatz(100000) |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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println((for (i <- 1 to 10000000) yield collatz(i).length).max) |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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println((for (i <- 1 to 10000000) yield collatz1(i)).max) |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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println((for (i <- 1 to 10000000) yield collatz2(i, 1)).max) |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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println((for (i <- (1 to 10000000).par) yield collatz2(i, 1)).max) |
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Christian Urban <christian dot urban at kcl dot ac dot uk>
parents:
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