28 lines
727 B
Nim
28 lines
727 B
Nim
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import sequtils, sets, strutils
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iterator recaman(num: Positive = Natural.high): tuple[n, a: int; duplicate: bool] =
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var a = 0
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yield (0, a, false)
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var known = [0].toHashSet
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for n in 1..<num:
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var next = a - n
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if next <= 0 or next in known:
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next = a + n
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a = next
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yield (n, a, a in known)
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known.incl a
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echo "First 15 numbers in Recaman’s sequence: ", toSeq(recaman(15)).mapIt(it.a).join(" ")
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for (n, a, dup) in recaman():
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if dup:
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echo "First duplicate found: a($1) = $2".format(n, a)
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break
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var target = toSeq(0..1000).toHashSet
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for (n, a, dup) in recaman():
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target.excl a
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if target.card == 0:
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echo "All numbers from 0 to 1000 generated after $1 terms.".format(n)
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break
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