#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdbool.h>
#include <math.h>


char* check_math_problem(const char* problem) {
    char* result_str = (char*)malloc(10 * sizeof(char)); 
    if (result_str == NULL) {
        fprintf(stderr, "Error with memory\n");
        exit(EXIT_FAILURE);
    }

    
    //char* copy = strcmp(problem);
    char* copy = (char*)malloc((strlen(problem) + 1) * sizeof(char));
    strcpy(copy, problem);
    if (copy == NULL) {
        fprintf(stderr, "Error with memory\n");
        exit(EXIT_FAILURE);
    }


    char* src = copy;
    char* dst = copy;
    while (*src != '\0') {
        if (*src != ' ') {
            *dst++ = *src;
        }
        src++;
    }
    *dst = '\0';

    
    if (strlen(copy) == 0) {
        free(copy);
        return "CHYBA";
    }
   
    
    double n1, n2, res;
    char sing, equel;
    
    if(sscanf(copy, "%lf%c%lf%c%lf", &n1, &sing, &n2, &equel, &res) !=5)
    {
        free(copy);
        return "CHYBA";
    }
   // printf("%lf%c%lf%c%lf", n1, sing, n2, equel, res);
    //return "1234";
    

    
    double result;
    switch (sing) {
        case '+':
            result = n1 + n2;
            break;
        case '-':
            result = n1 - n2;
            break;
        case '*':
            result = n1 * n2;
            break;
        case '/':
            if (fabs(n2) < 1e-9) { 
                free(copy);
                return "ZLE";
            }
            result = n1 / n2;
            break;
        default:
            free(copy);
            return "CHYBA";
    }

    
    if (fabs(result - res) < 0.01) {
        strcpy(result_str, "OK");
    } else {
        strcpy(result_str, "ZLE");
    }

    free(copy);
    return result_str;
}

int main() {
    char problem[100]; 

    
    while (true) {
        fgets(problem, sizeof(problem), stdin);
        if (strlen(problem) == 1) { 
            break;
        }
        printf("%s\n", check_math_problem(problem));
    }

    return 0;
}