mirror of
https://github.com/TheAlgorithms/Ruby
synced 2024-12-26 21:58:56 +01:00
42 lines
1 KiB
Ruby
42 lines
1 KiB
Ruby
# A ruby program for 3N plus 1
|
|
# 3N plus 1 is also called as Collatz Conjecture
|
|
#
|
|
# f(n) => n / 2 (if n = 0 (mod 2))
|
|
# f(n) => (3n + 1) (if n = 1 (mod 2))
|
|
#
|
|
# Wiki: https://en.wikipedia.org/wiki/Collatz_conjecture
|
|
|
|
def collatz_conjecture(number)
|
|
n = number
|
|
nums = Array.new
|
|
nums.push number
|
|
while number > 1
|
|
if number % 2 == 0
|
|
number /= 2
|
|
nums.push number
|
|
else
|
|
number = 3 * number + 1
|
|
nums.push number
|
|
end
|
|
end
|
|
"The 3N + 1 series of #{n} is #{nums.to_s}."
|
|
rescue
|
|
"Error: Please provide number only!"
|
|
end
|
|
|
|
# Valid inputs
|
|
puts collatz_conjecture(12)
|
|
# The 3N + 1 series of 12 is [12, 6, 3, 10, 5, 16, 8, 4, 2, 1].
|
|
|
|
puts collatz_conjecture(6)
|
|
# The 3N + 1 series of 6 is [6, 3, 10, 5, 16, 8, 4, 2, 1].
|
|
|
|
puts collatz_conjecture(100)
|
|
# 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].
|
|
|
|
# Invalid inputs
|
|
puts collatz_conjecture("12")
|
|
# Error: Please provide number only!
|
|
|
|
puts collatz_conjecture("a")
|
|
# Error: Please provide number only!
|