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

int main() {

    char line[256];

    while (fgets(line, sizeof(line), stdin) != NULL) {
      //nothing
        line[strcspn(line, "\n")] = 0;
//empty line

        if (strlen(line) == 0) {
            break;
        }

      //nospace
        char pusto[256];
        int j = 0;
        for (int i = 0; line[i] != '\0'; i++) {
            if (!isspace(line[i])) {
                pusto[j++] = line[i];
            }
        }
        pusto[j] = '\0';

        // Parse
        double n1;
        double n2;
        double expect;
        char op;
        int parsed = sscanf(pusto, "%lf%c%lf=%lf", &n1, &op, &n2, &expect);

        if (parsed != 4) {
            printf("CHYBA\n");
            continue;
        }
// is valid
        if (op != '+' && op != '-' && op != '*' && op != '/') {
            printf("CHYBA\n");
            continue;
        }

       // resultat ye
        double teraz;
        switch (op) {
            case '+':
                teraz = n1 + n2;
                break;
            case '-':
                teraz = n1 - n2;
                break;
            case '*':
                teraz = n1 * n2;
                break;
            case '/':
                if (n2 == 0.0) {
                 
                    printf("ZLE\n");
                    continue;
                }
                teraz = n1 / n2;
                break;
        }

        // zaokrouhleni
        double rounded_teraz = round(teraz * 100.0) / 100.0;
        double rounded_expect = round(expect * 100.0) / 100.0;

        if (fabs(rounded_teraz - rounded_expect) < 1e-9) {
            printf("OK\n");
        } else {
            printf("ZLE\n");
        }
    }
    return 0;
}