# --------------------------------------------------------- rpn3.rb ^

print "RPN CALC #4 of ruby, ready.    by guel  02/20/99\n"


class RpnCalc
	include Math
	def initialize
		@s = []
	end
	def set(x)
		@s.push x.to_f
	end
	def add
		@s.push @s.pop + @s.pop
	end
	def multi
		@s.push @s.pop * @s.pop
	end
	def sub
		@s.push (-@s.pop + @s.pop)
	end
	def div
		@s.push 1 / @s.pop / @s.pop
	end
	def set_PI
		@s.push PI
	end
	def set_E
		@s.push E
	end
	def sin
		@s.push super(@s.pop)
	end
	def cos
		@s.push super(@s.pop)
	end
	def tan
		@s.push super(@s.pop)
	end
	def exp
		@s.push super(@s.pop)
	end
	def log
		@s.push super(@s.pop)
	end
	def log10
		@s.push super(@s.pop)
	end
	def sqrt
		@s.push super(@s.pop)
	end
	def show
		p @s
	end
end


rpncalc = RpnCalc.new

while gets
	split.each do |x|
	begin
		case x
			when /\d/
				rpncalc.set x
			when 'pi','PI'
				rpncalc.set_PI
			when 'e','E'
				rpncalc.set_E
			when '+'
				rpncalc.add
			when '*'
				rpncalc.multi
			when '-'
				rpncalc.sub
			when '/'
				rpncalc.div
			when 'sin'
				rpncalc.sin
			when 'cos'
				rpncalc.cos
			when 'tan'
				rpncalc.tan
			when 'exp'
				rpncalc.exp
			when 'log'
				rpncalc.log
			when 'log10'
				rpncalc.log10
			when 'sqrt'
				rpncalc.sqrt
			else
				print "入力がヘンだぜ (^^;\n"
				p x
		end
	rescue
		print "例外処理が発生！！\n"
		p $!
		p $@
	end
	end
	rpncalc.show

end

# --------------------------------------------------------- rpn3.rb $