#include <stdlib.h>
#include <stdio.h>
#include <math.h>
#include <conio.h>
#include <string.h>
 
//************************** stack ****************************************
struct stack
{
    char info;
    stack *link;
}*ss;
//************************** stack ****************************************
struct stack2
{
    long info;
    stack2 *link;
}*ss2;
//************************** num ***************************************
struct number
{
    long value;
    char chr;
    number *link;
}*ns;
//************************** check num **********************************
long checknum(char chr)
{
    number *ptr;
    ptr = ns;
    while ( ptr != NULL)
    {
        if ( ptr->chr == chr) return ptr->value;
        ptr = ptr->link;
    }
    return 0;
}
//************************** insert num **********************************
void insertnum(long value, char chr)
{
    number *ptr;
    ptr = (number*) malloc(sizeof(number));
    ptr->link = ns;
    ptr->chr = chr;
    ptr->value = value;
    ns = ptr;
}
//************************** push ***************************************
void push(char item)
{
    stack *ptr;
    ptr = (stack*) malloc(sizeof(stack));
    ptr->info = item;
    ptr->link = ss;
    ss = ptr;
}
//************************** pop ****************************************
char pop()
{
    stack *ptr;
    ptr = ss;
    char temp;
    temp = ss->info;
    ss = ss->link;
    free(ptr);
    return temp;
}
//************************** push ***************************************
void push2(long item)
{
    stack2 *ptr;
    ptr = (stack2*) malloc(sizeof(stack2));
    ptr->info = item;
    ptr->link = ss2;
    ss2 = ptr;
}
//************************** pop ****************************************
long pop2()
{
    stack2 *ptr;
    ptr = ss2;
    long temp;
    temp = ss2->info;
    ss2 = ss2->link;
    free(ptr);
    return temp;
}
//************************** mid ****************************************
char mid ( char source[] , int position , int count , char destination[])
{
    int qcount = 0 , len ;
    len = strlen(source);
    for ( int i = position - 1 ; i < position + count - 1 && i < len ; i++ , qcount++)
        destination[qcount] = source[i];
    destination[qcount] = 0; 
    if ( qcount == 1) return destination[0];
    else return 0;
}
//************************** priority **************************************
int priority(char a , char b)
{
    if ( a == '^') return 1;
    if ( b == '^') return 0;
    if ( a == '*' || a == '/' || a == '%' ) return 1;
    if ( b == '*' || b == '/' || b == '%' ) return 0;
    return 1;
}
//************************** pulish ****************************************
void pulish(char source[] , char dest[] , int len)
{
    char temp , temp2[2];
    int count = 0;
    for ( int i = 0 ; i < len ; i++)
    {
        temp = mid(source , i + 1 , 1 , temp2);
        switch (temp)  
        {
        case '+':
        case '-':
        case '*':
        case '/':
        case '^':
        case '%':
            if (ss->info == '(' || priority(ss->info , temp) == 0 ) push (temp);
            else
            {
                while (ss ->info != '(' && priority(ss->info , temp))
                    dest[count++] = pop();
                push(temp);
            }
        break;     
        case '(':
            push(temp);
        break;
         
        case ')':
            while ( ss->info != '(')
                dest[count++] = pop();
            pop();
        break;
        default :
            if ( temp >= 48 && temp <= 122)
                dest[count++] = temp;
        }                
    }
    dest[count] = 0;
}
//************************** value ****************************************
long value(char source[] , int len)
{
    char temp , temp2[2] ;
    long a , b, result;
    for ( int i = 0 ; i < len ; i++)
    {
        temp = mid ( source , i + 1 , 1 , temp2);
        if ( temp >= 48 && temp <= 122)
        {
            a = checknum(temp);
            if ( a == 0 )
            {
                printf("Please Enter %c =" , temp);
                scanf("%u" ,&a);
                insertnum(a , temp);
                push2(a);
            }
            else push2(a);
        }
        else
        {
            b = pop2();
            a = pop2();
            switch (temp)
            {
            case '+':
                result = a + b;
                push2 (result);
            break;
            case '-':
                result = a - b;
                push2 (result);
            break;
            case '*':
                result = a * b;
                push2 (result);
            break;
            case '/':
                result = a / b;
                push2 (result);
            break;
            case '^':
                result = pow(a,b);
                push2 (result);
            break;
            case '%':
                result = a % b;
                push2 (result);
            break;
            }
        }
    }
    return pop2();
}
//************************** main ****************************************
int main()
{
    char p[102] , q[100];
    clrscr();
    int len;
  cin>> p;
    len = strlen(p);
    for ( int i = len ; i > 0 ; i--)
    p[i] = p[i-1];
    p[0] = '(';
    p[len + 1] = ')';
    len +=2;
    p[len] = 0;
    pulish ( p , q , len);
    len = strlen(q);
    cout<< value ( q , len);
    getch();
    return 0;
}