#include <iostream>
#include <stack>
#include <string.h>
#include <stdio.h>
#include <fstream>
using namespace std;
ifstream fin("evaluare.in");
ofstream fout("evaluare.out");
stack<char> stac;
bool isPriority(char a,char b)
{
    if((a=='+' || a=='-') && (b=='*' || b=='/'))
        return false;
    if((b=='+' || b=='-') && (a=='*' || a=='/'))
        return true;
    return false;
}
bool isDigit(char a)
{
    if(a>='0'&& a<='9')
        return true;
    return false;
}
string infixToPostFix(string a)
{
    string res;
    for(int i = 0; i< a.size(); i++)
    {
        if(isDigit(a[i]))
        {
            res+=a[i];
            if(i!=a.size()-1)
            {
                if(!isDigit(a[i+1]))
                    res+=" ";
            }
            else
            {
                res+=" ";
            }
        }
        else
        {
            if(a[i]==')')
            {
                while(stac.size() && stac.top()!='(')
                    res+=stac.top(),stac.pop();
                if(stac.size())
                    stac.pop();
            }
            else
            {
                while(stac.size() && isPriority(stac.top(),a[i]))
                {
                    if(stac.top()!='(')
                        res+=stac.top();
                    stac.pop();
                }
                stac.push(a[i]);
            }
        }
    }
    while(stac.size())
            res+=stac.top(),stac.pop();
    return res;
}
stack<long long> numere;
long long solvePostFix(string a)
{
    long long b=0;
    for(int i = 0;i<a.size();i++)
    {
        if(isDigit(a[i]))
            b*=10,b+=((int)a[i]-(int)'0');
        else if(a[i]==' ')
            numere.push(b),b=0;
        else
        {
            long long num1,num2,res=0;
            num1=numere.top();
            numere.pop();
            num2=numere.top();
            numere.pop();
            switch(a[i])
            {
                case '+':
                    res = num1+num2;
                    break;
                case '-':
                    res = num1-num2;
                    break;
                case '/':
                    res = num2/num1;
                    break;
                case '*':
                    res = num1*num2;
                    break;
            }
            numere.push(res);
        }
    }
    return numere.top();
}
int main()
{
    string a;
    fin>>a;
    fout<<solvePostFix(infixToPostFix(a))<<'\n';
    return 0;
}