Class: Partitions

Inherits:
Object
  • Object
show all
Defined in:
lib/partitions.rb

Instance Method Summary collapse

Instance Method Details

#enumerates(n) ⇒ Object 



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# File 'lib/partitions.rb', line 3

def enumerates(n)
  partitions = {}
  partitions[1] = [[1]]
  2.upto(n) do |value|
    partitions[value] = partition(value, partitions)
  end
  partitions[n]
end

#partition(n, previous) ⇒ Object 



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# File 'lib/partitions.rb', line 12

def partition(n, previous)
  result = [[n]]
  (n - 1).downto(1) do |value|
    result.concat(sumfy(value, previous[n - value]))
  end
  result
end

#sumfy(number, partitions) ⇒ Object 



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# File 'lib/partitions.rb', line 20

def sumfy(number, partitions)
  result = []
  partitions.each do |partition|
    result << ([number] + partition) if (number >= partition.first)
  end
  result
end