/* Algo - TP3 */
/* Module principal */

#include <stdio.h>
#include <stdlib.h>
#include "listes.h"
#include "liste_ext.h"
#include "stack.h"
#include <errno.h>

double evaluer_operation (char *e)
{
    stack s ;
    char *fin ;
    long n ;
    int a, b ;

    create_empty_stack (&s) ;
    while (*e != '\0') {
        n = strtol (e, &fin, 10) ;
        if ((n != 0)) {
            push (n, &s) ;
            e = fin ;
        } else {
            if (*e == ' ') *e++ ;
            if (*e == '+') {
                a = pop (&s) ;
                b = pop (&s) ;
                push (a + b, &s) ;
                *e++ ;
            } else if (*e == '-') {
                a = pop (&s) ;
                b = pop (&s) ;
                push (a - b, &s) ;
                *e++ ;
            } else if (*e == '*') {
                a = pop (&s) ;
                b = pop (&s) ;
                push (a * b, &s) ;
                *e++ ;
            } else if (*e == '/') {
                a = pop (&s) ;
                b = pop (&s) ;
                push (a / b, &s) ;
                *e++ ;
            }
        }
    }

    a = pop (&s) ;
    return a ;
}

int main ()
{
    char *expr = "1 4 5 + * 3 2 * +" ;
    double res ;

    res = evaluer_operation (expr) ;
    printf ("%lf", res) ;

    return 0 ;
}