#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>

#define STACK_SIZE 10

struct stack{
    float values[STACK_SIZE];
    int size;
};

void push_stack(struct stack *s, float value){
    if (s->size >= STACK_SIZE){
        printf("Chyba: zasobnik je plny!\n");
        exit(1);
}
    s->values[s->size] = value;
    s->size++;
    }

float pop_stack(struct stack *s){
    if (s->size <= 0){
        printf("Chyba: zasobnik je prazdny!\n");
        exit(1);
}
    s->size--;
    return s->values[s->size];
    }

void print_stack(struct stack *s){
    for (int i = 0; i < s->size; i++){
        printf("%.2f ", s->values[i]);
        }
    printf("\n");
    }

int main(){
    struct stack s;
    s.size = 0;

    char input[100];

    while (1){
        if (scanf("%s", input) != 1){
            printf("Chyba: nepodarilo sa nacitat vstup.\n");
            return 1;
            }

        char *endptr;
        float value = strtof(input, &endptr);

            if (*endptr == '\0') {
            push_stack(&s, value);
            print_stack(&s);
            } 
        else if (strcmp(input, "+") == 0){
            if (s.size < 2){
                printf("Chyba: malo hodnot v zasobniku!\n");
                return 1;
                }
            float b = pop_stack(&s);
            float a = pop_stack(&s);
            push_stack(&s, a + b);
            print_stack(&s);
            } 
        else if (strcmp(input, "-") == 0){
            if (s.size < 2){
                printf("Chyba: malo hodnot v zasobniku!\n");
                return 1;
                }
            float b = pop_stack(&s);
            float a = pop_stack(&s);
            push_stack(&s, a - b);
            print_stack(&s);
            } 
        else if (strcmp(input, "*") == 0){
            if (s.size < 2){
                printf("Chyba: malo hodnot v zasobniku!\n");
                return 1;
                }
            float b = pop_stack(&s);
            float a = pop_stack(&s);
            push_stack(&s, a * b);
            print_stack(&s);
            } 
        else if (strcmp(input, "/") == 0){
            if (s.size < 2){
                printf("Chyba: malo hodnot v zasobniku!\n");
                return 1;
                }
            float b = pop_stack(&s);
            float a = pop_stack(&s);
            if (b == 0){
                printf("Chyba: delenie nulou!\n");
                return 1;
                }
            push_stack(&s, a / b);
            print_stack(&s);
            } 
        else{
            printf("Chyba: neplatny vstup '%s'\n", input);
            return 1;
            }
            }
    return 0;
}