RPN Calculator

RPN Calculator

class RPNCalculator
  
  def evaluate(input)
    array = input.split
      
      array.each do |x|
        case 
         
        when x == "+"
          op_index = array.index(x)
          add = array[op_index-2].to_i + array[op_index - 1].to_i
          array.insert(op_index + 1, add)
          array.slice!(op_index -2, op_index)
          
          puts array.inspect
          puts op_index

        when x == "-"
          op_index = array.index(x)
          minus = array[op_index-2].to_i - array[op_index - 1].to_i
          array.insert(op_index + 1, minus)
          array.slice!(op_index -2, op_index)
          
          puts array.inspect
          puts op_index

        when x == "*"
          op_index = array.index(x)
          multi = array[op_index-2].to_i * array[op_index - 1].to_i
          array.insert(op_index + 1, multi)
          array.slice!(op_index -2, op_index)
          
          puts array.inspect
          puts op_index
        else  

        end
      end
        #array.first.to_i
  end
end

#calc = RPNCalculator.new
#puts calc.evaluate('1 2 +')
#calc = RPNCalculator.new
#puts calc.evaluate('2 5 *')
calc = RPNCalculator.new
puts calc.evaluate('70 10 4 + 5 * -')