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

int main() {
    char line[256];

    while (fgets(line, sizeof(line), stdin) != NULL) {
        if (line[0] == '\n' || line[0] == '\r') break;

        double a, b, result;
        char op;
        char eq;
        char extra;

        int n = 0;
        int parsed = sscanf(line, " %lf %c %lf %c %lf %c%n", &a, &op, &b, &eq, &result, &extra, &n);

        if (parsed != 5 || eq != '=') {
            printf("CHYBA\n");
            continue;
        }

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

        double actual;
        if      (op == '+') actual = a + b;
        else if (op == '-') actual = a - b;
        else if (op == '*') actual = a * b;
        else                actual = a / b;

        double rounded_actual = round(actual * 100.0) / 100.0;
        double rounded_result = round(result * 100.0) / 100.0;

        if (fabs(rounded_actual - rounded_result) < 1e-9) {
            printf("OK\n");
        } else {
            printf("ZLE\n");
        }
    }

    return 0;
}