/* 
 * File:   main.cpp
 * Author: SpeeDemon
 *
 * Created on April 5, 2010, 4:50 PM
 */
#include <stack>
#include <sstream>
#include <fstream>

/*
 *
 */
using namespace std;
inline int priority( char x )
{
    if( '(' == x )
        return 0;
    if( '+' == x || '-' == x )
        return 1;
    if( '*' == x || '/' == x )
        return 2;
    return 5;
}
inline string transform( string* expresion )
{
    int p;
    stack< char > v;
    ostringstream t;
    string::const_iterator it=expresion->begin(), iend=expresion->end();
    while( it < iend )
    {
        if( *it >= '0' && *it <= '9' )
        {
            for( ; *it >= '0' && *it <= '9' && it < iend; ++it )
                t<<*it;
            t<<' ';
            continue;
        }
        if( '(' == *it )
        {
            v.push(*it), ++it;
            continue;
        }
        if( ')' == *it )
        {
            ++it;
            while(  '(' != v.top() )
                 t<<v.top(), v.pop();
            v.pop();
            continue;
        }
        p=priority( *it );
        while( !v.empty() && p <= priority( v.top() ) )
            t<<v.top(), v.pop();
        v.push( *it );
        ++it;
    }
    while( !v.empty() )
        t<<v.top(), v.pop();
    return t.str();
}
inline int evaluate( string *expresion )
{
    *expresion=transform( expresion );
    stack< int > s;
    int number, a, b;
    string::const_iterator it=expresion->begin(), iend=expresion->end();
    for( ; it < iend; ++it )
    {
        if( *it >= '0' && *it <= '9' )
        {
            for( number=0; *it >= '0' && *it <= '9'; ++it )
                number=number*10+*it-'0';
            s.push(number);
            continue;
        }
        b=s.top(); s.pop();
        a=s.top(); s.pop();
        switch( *it )
        {
            case '+' : s.push(a+b); break;
            case '-' : s.push(a-b); break;
            case '*' : s.push(a*b); break;
            case '/' : s.push(a/b); break;
        }
    }
    return s.top();
}
int main( void )
{
    string expresion;
    ifstream in( "evaluare.in" );
    getline( in, expresion );
    ofstream out( "evaluare.out" );
    out<<evaluate( &expresion )<<'\n';
    return EXIT_SUCCESS;
}