#include <iostream>
#include <stack>

int main()
{
    char s[101];
    std::cin >> s;
    
    std::stack<char> stk;

    for(int i = 0; s[i]; i++)
    {
        if((s[i] > '0') && (s[i] < '9'))
            s[i] -= '0';
        
        stk.push(s[i]);
    }
    
    int ans = 0;
    int temp = 0;
    int sign = 0;
    char pop;
    
    while(!stk.empty())
    {
        pop = stk.top();
        stk.pop();
        if(pop <= 9)
        {
            switch(sign)
            {
                case 0:  ans = pop; break;
                case 1:  ans += pop; break;
                case -1: ans = pop - ans;
            }
            sign = 0;
        }
        if(pop == '+')
            sign = 1;
        if(pop == '-')
            sign = -1;
        
        if(pop == ')')
        {
            temp = ans * sign;
            sign = 0;
        }
        if(pop == '(')
        {
            stk.push(ans);
            stk.push('+');
            stk.push(temp);
            sign = 0;
            ans = 0;
        }
    }
    
    std::cout << ans << std::endl;
    
    return 0;
}