Sunny.Dackie.Compact.rb

#This is compact version of my previous solution <http://gist.github.com/258571>
# If compactness is what this challange looking for then this would be suffice
# However I would not recommend as it is not readable though it passes all the tests
# Same logic as in <http://gist.github.com/258571> but written to be compact
 
class Polynomial 
	def initialize(coefficients)
		s = false; p = 0; @expression = "";
		coefficients.reverse_each do |c|
			if c!=0
				@expression += (s ? "+" : "") + (p>1 ? "#{p}^" : "") + (p>0 ? "x" : "") + ((p >0 && c.abs==1) ? "" : ("#{c}".reverse)) + ((c==-1) ? "-" : "") 
				s = (c>0) ? true : false 
			end
      p = p + 1
		end
		raise ArgumentError, "Need at least 2 coefficients" unless p > 1
	end
 
	def to_s
		return @expression=="" ? "0" :  @expression.reverse        # Return 0 as required 
	end
end