func main()
	var s: []char :: cui@input()
	var state: int :: 0
	var a: int
	var b: int
	var op: char
	var aop: char :: '+'
	var bop: char :: '+'
	for i(0, ^s - 1)
		switch(state)
		case 0
			if(s[i] = '-' | s[i] = '+')
				do aop :: s[i]
			else
				do i :- 1
			end if
			do state :+ 1
		case 1
			if(s[i] = '-' | s[i] = '+')
				do i :- 1
				do state :+ 1
			else
				do a :* 10
				do a :+ s[i] $ int - '0' $ int
			end if
		case 2
			do op :: s[i]
			do state :+ 1
		case 3
			if(s[i] = '-' | s[i] = '+')
				do bop :: s[i]
			else
				do i :- 1
			end if
			do state :+ 1
		case 4
			do b :* 10
			do b :+ s[i] $ int - '0' $ int
		end switch
	end for
	if(aop = '-')
		do a :: -a
	end if
	if(bop = '-')
		do b :: -b
	end if
	
	var ans: int :: 0
	if(op = '-')
		do ans :: a + b
	else
		do ans :: a - b
	end if
	do cui@print("\{ans}\n")
end func