import Foundation
let input = Array(readLine()!)
var array : Array<String> = []
var sum = ""
for (index, value) in input.enumerated() {
if value == "-" || value == "+" {
array.append(sum)
sum = ""
array.append(String(value))
}else{
sum += String(value)
}
if index == input.count-1 {
array.append(sum)
}
}
var answer = 0
var min = 0
var isMinus : Bool = false
for (index,value) in array.enumerated() {
if array[index] == "-" {
isMinus = true
}else if array[index] == "+"{
}
else{
if isMinus {
min -= Int(array[index])!
}else{
min += Int(array[index])!
}
}
}
print(min)