import java.io.BufferedReader;
import java.io.InputStreamReader;
class Main1541 {
public static void main(String[] args) throws Exception {
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
int ans = 0;
String[] split = br.readLine().split("-");
for (int i = 0; i < split.length; i++) {
int sum = 0;
String[] split2 = split[i].split("\\+");
for (String sub2 : split2) {
sum += Integer.parseInt(sub2);
}
if (i == 0) {
ans += sum;
} else {
ans -= sum;
}
}
System.out.println(ans);
}
}
휴지통/알고리즘 & 자료구조