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

#define MAX_LENGTH 100

int check(char* input);

int main() {
    char input[MAX_LENGTH];
    while (fgets(input,MAX_LENGTH, stdin)) {
        if (input[0] == '\n') {
            break;
          }
         input[strcspn(input, "\n")] = '\0';
         int resultat =check(input);
         if (resultat ==1) {
            printf("OK\n");
          } else {
             if (resultat == -1) {
                  printf("ZLE\n");
              } else {
                 printf("CHYBA\n");
             }
           }
       }
    return 0;
}

int check(char* input) {
    double number1, number2, resultat, givenResult;
    char znak;
    int a=0;
     a=sscanf(input, " %lf %c %lf = %lf ", &number1, &znak, &number2, &givenResult);
     if (input == NULL || strlen(input) == 0 || strspn(input, " \t\n") == strlen(input)) {
        return 0;
             }
       if (a != 4) {
        return 0;
        }else {
        switch (znak) {
            case '+':
                resultat=number1+number2;
            break;
            case '-':
                resultat=number1-number2;
            break;
            case '*':
                resultat=number1*number2;
            break;
            case '/':
                if (number2 == 0) {
                    return 0;
                   }else{resultat=number1/number2;}
            break;
            default:
            return 0;
              }
       }
       if (resultat-givenResult ==0 ) {
        return 1;
       } else { return -1;
          }
 }