25 lines
547 B
Plaintext
25 lines
547 B
Plaintext
func hailstone (n) {
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var sequence = [n]
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while (n > 1) {
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sequence << (
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n.is_even ? n.div!(2)
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: n.mul!(3).add!(1)
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)
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}
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return(sequence)
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}
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# The hailstone sequence for the number 27
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var arr = hailstone(var nr = 27)
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say "#{nr}: #{arr.first(4)} ... #{arr.last(4)} (#{arr.len})"
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# The longest hailstone sequence for a number less than 100,000
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var h = [0, 0]
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for i (1 .. 99_999) {
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(var l = hailstone(i).len) > h[1] && (
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h = [i, l]
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)
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}
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printf("%d: (%d)\n", h...)
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