#codality35 CommonPrimeDivisors

gistfile1.txt

#codality35  CommonPrimeDivisors

require 'prime'

a = [15, 10, 3, 2]
b = [75, 30, 5, 8]


def solution(a, b)
  
  if a.max > b.max
    max = a.max
  else
    max = b.max
  end

  primeArray = []
  Prime.each(max/2) do |prime|
    primeArray.push(prime)
  end
  
  result = ""
  i = 0
  while i < a.count
    factorArrayA = []
    if primeArray.include?(a[i])
      factorArrayA.push(a[i])
    else
      truncatedArray = primeArray.take_while { |n| n <= a[i] / 2 }
    # We only need to check primes that are 1/2 the size of the selected number from the array
    # Then we check each if each of the primes are factors of the number
        truncatedArray.each do |prime|
        if a[i].modulo(prime)  == 0
          factorArrayA.push(prime)
        end
      end
    end

      # I do the same logic for the b array. This is not dry buy I do not see a good answer right now

    factorArrayB = []
    if primeArray.include?(b[i])
      factorArrayB.push(b[i])
    else
      truncatedArray = primeArray.take_while { |n| n <= b[i] / 2 }
      truncatedArray.each do |prime|
        if b[i].modulo(prime)  == 0
          factorArrayB.push(prime)
        end
      end
    end
 
    
    if factorArrayB == factorArrayA
      result = result + "(#{a[i]}, #{b[i]})"
    end

  i += 1
  end 




  return result
end


puts "These pairs have common factors #{solution(a, b)}"