#include <stdio.h>
int n, v, w, x, s[99]; char c;
int main() {
	while (c = getchar()) {
		if (c == '(') s[n++] = v, w ^= v, v = 0;
		else if (c == ')') w ^= s[--n];
		else if (c == '+') v = 0;
		else if (c == '-') v = 1;
		else if ('0' <= c && c <= '9') x += (w ^ v ? 48 - c : c - 48);
		else break;
	}
	printf("%d\n", x);
}