class that pretty-prints polynomials

SurajDhakankar.rb

class Polynomial
	attr_accessor :expression

	def initialize(coeffs)
  
		bConstant = true	#Print constant value of the polynomial
		bPower = false		#Print variable x with its power > 1
		bSign = false		#Print + as it does not get printed while printing positive integer
		index = 0		#Contains power of the variable x in polynomial
		expression = ""		#Polynomial expression to be created in reverse order
		
		#Start creating polynomial from least power of x to 
		#highest power of x in reverse order
		coeffs.reverse_each do |coeff|
		
			#Print + sign if required for the previous coefficient
			expression += (bSign && coeff!=0) ? "+" : ""
			
			#For an element of polynomial Ax^N print "^N" in reverse 
			#order where N>1 and A!=0
			expression += (bPower && coeff!=0) ? "#{index}^" : ""
		
			if bConstant
				#Print constant term of polynomial if non-zero
				expression += (coeff != 0) ? "#{coeff}".reverse : ""
				bConstant = false
			else
				#For an element of polynomial Ax^N print "Ax" in reverse order where A!=0
				#Handle special cases of A==-1 and A==1
				expression += (coeff != 0) ? ( coeff ==1?"x":(coeff ==-1?"x-":"#{coeff}x".reverse)): ""
				bPower = true
			end
	
			#If current coefficient is positive we need to print the '+' sign 
			#while printing next higher term of polynomial
			#'-' sign for current coefficient gets printed while printing the number
			if coeff != 0
				bSign= (coeff>0) ? true : false
			end
			
			#increment power of variable x to next level
			index += 1
		end
		
		if bPower
			#Handle the case when all the coefficients are zero
			@expression = (expression!="") ? expression.reverse : "0"
		elsif
			#raise exception if there are less than 2 coefficients
			raise ArgumentError, "Need at least 2 coefficients"
		end	
	end

	def to_s
		return @expression
	end
end