8.2.rb

def getIndex(string)
  string.split(" ").first.to_i
end
def getString(string)
  string.split(" ").last
end
def fms(array)
  return array if array.length==1
  
  first_subarray_limit=(array.length.to_f/2).floor
  second_subarray_limit=(array.length.to_f/2).ceil
  first_subarray_limit-=1 if first_subarray_limit == second_subarray_limit 
  
  array1=fms(array[0..first_subarray_limit])
  array2=fms(array[second_subarray_limit..array.length])
  
  sorted_array=[]
  
  while not array1.empty? or not array2.empty? 
    sorted_array<< array1.shift if (array2.empty? and not array1.empty?) or (not array1.empty? and getIndex(array1.first)<=getIndex(array2.first))
    sorted_array<< array2.shift if (array1.empty? and not array2.empty?) or (not array2.empty? and getIndex(array1.first)>getIndex(array2.first))
  end
  sorted_array

end
def full_merge_sort(array)
  # write your code here
  array=fms(array)
  result=[]
  array.each do |element|
    result<< getString(element)
  end
  result
end

full_merge_sort(["0 ab", "6 cd", "0 ef", "6 gh", "4 ij", "0 ab", "6 cd", "0 ef", "6 gh", "0 ij", "4 that", "3 be", "0 to", "1 be", "5 question", "1 or", "2 not", "4 is", "2 to", "4 the"])
# => ["ab", "ef", "ab", "ef", "ij", "to", "be", "or", "not", "to", "be", "ij", "that", "is", "the", "question", "cd", "gh", "cd", "gh"]