Code Kata Two solutions

chop.rb

class Chop
	def chop(target, values)
		size = values.size

		if size == 0
			-1
		elsif size == 1
			(values[0] == target ? 0 : -1)
		else
			if target < values[size/2]
				chop(target, values[0..size/2-1])
			else
				result = chop(target, values[size/2..size])
				(result != -1 ? size/2 + result : -1)
			end
		end
	end
end

These are my attempts at CodeKata two solutions.

-The first is iterative
-The second is recursive
-The third (4th commit) is recursive and a little different