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https://github.com/TheAlgorithms/Ruby
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44 lines
1 KiB
Ruby
44 lines
1 KiB
Ruby
# A ruby program for 3N plus 1
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# 3N plus 1 is also called as Collatz Conjecture
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#
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# f(n) => n / 2 (if n = 0 (mod 2))
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# f(n) => (3n + 1) (if n = 1 (mod 2))
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#
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# Wiki: https://en.wikipedia.org/wiki/Collatz_conjecture
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def collatz_conjecture(number)
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n = number
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nums = []
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nums.push(number)
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while number > 1
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if number.even?
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number /= 2
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nums.push(number)
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else
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number = 3 * number + 1
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nums.push(number)
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end
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end
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"The 3N + 1 series of #{n} is #{nums}."
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rescue StandardError
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'Error: Please provide number only!'
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end
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# Valid inputs
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puts collatz_conjecture(12)
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# The 3N + 1 series of 12 is [12, 6, 3, 10, 5, 16, 8, 4, 2, 1].
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puts collatz_conjecture(6)
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# The 3N + 1 series of 6 is [6, 3, 10, 5, 16, 8, 4, 2, 1].
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puts collatz_conjecture(100)
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# The 3N + 1 series of 100 is [100, 50, 25, 76, 38, 19, 58, 29, 88, 44, 22, 11, 34, 17, 52, 26, 13, 40, 20, 10, 5, 16, 8, 4, 2, 1].
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# Invalid inputs
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puts collatz_conjecture('12')
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# Error: Please provide number only!
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puts collatz_conjecture('a')
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# Error: Please provide number only!
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