Merge Sort with so Debugging Statements I pulled this from the web somewhere but I don't remember the URL and made some modifications

mergsort_coursera_algo

a = [5,4,1,8,7,2,6,3,5,2,3,45,1,1,3,4,99,2,3]
puts a.size
@recurse = 0

def mergesort(list)
  return list if list.size <= 1
  mid = list.size / 2
  left  = list[0, mid]
  right = list[mid, list.size]
  @recurse = @recurse + 1
  puts @recurse
  merge(mergesort(left), mergesort(right))
end

def merge(left, right)
  sorted = []
  until left.empty? or right.empty?
    if left.first <= right.first
      #puts "inversion"
      sorted << left.shift
    else
    	#puts "inversion"
      sorted << right.shift
    end
  end
  sorted.concat(left).concat(right)
end

puts mergesort a