18 lines
481 B
Plaintext
18 lines
481 B
Plaintext
def hailstone(n)
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seq = [n]
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until n == 1
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n = n.even? ? n / 2 : n * 3 + 1
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seq << n
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end
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seq
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end
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max_len = (1...100_000).max_by{|n| hailstone(n).size }
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max = hailstone(max_len)
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puts ([max_len, max.size, max.max, max.first(4), max.last(4)])
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# => [77031, 351, 21933016, [77031, 231094, 115547, 346642], [8, 4, 2, 1]]
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twenty_seven = hailstone(27)
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puts ([twenty_seven.size, twenty_seven.first(4), max.last(4)])
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# => [112, [27, 82, 41, 124], [8, 4, 2, 1]]
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