import strutils, sequtils, future, algorithm

var
  s=stdin.readLine
  res=0
  stack=newSeq[char]()

for i in countdown(s.len-1, 0):
  if s[i]=='(':
    var
      ret=stack.pop.ord-'0'.ord
      c=stack.pop
    while c!=')':
      if c=='+':
        ret+=stack.pop.ord-'0'.ord
      else:
        ret-=stack.pop.ord-'0'.ord
      c=stack.pop
    stack.add((ret+'0'.ord).chr)
  else:
    stack.add(s[i])

reverse(stack)
res=stack[0].ord-'0'.ord
for i in 1..<stack.len:
  if stack[i]=='+':
    res+=stack[i+1].ord-'0'.ord
  elif stack[i]=='-':
    res-=stack[i+1].ord-'0'.ord

echo res