#include <stdio.h>

int main() {
    int ans=0;
    int tmp;
    int *tg = &ans;
    int next=1;
    int tb=1;
    char c;
    while((c=getchar()) != '\n') {
        switch (c) {
        case '+':
            next=1;
            break;
        case '-':
            next=-1;
            break;
        case '(':
            tb=next;
            next=1;
            tmp=0;
            tg=&tmp;
            break;
        case ')':
            ans+=(tmp*tb);
            tg=&ans;
            next=1;
            tb=1;
            break;
        default:
            (*tg)+=((c-'0')*next);
        }
    }
    printf("%d\n", ans);
    return 0;
}