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

int call(double A, double B, double C, char AC){
    if(AC=='/'&&B==0){
        return printf("CHYBA");;
    }
    if(AC=='+'){
        if(A+B==C)return printf("OK");
        return printf("ZLE");
    }
    if(AC=='-'){
        if(A-B==C)return printf("OK");
        return printf("ZLE");
    }
    if(AC=='*'){
        if(A*B==C)return printf("OK");
        return printf("ZLE");
    }
    if(AC=='/'){
        if(A/B==C)return printf("OK");
        return printf("ZLE");
    }    
}

int main()
{
    

char *str;
str=(char*)malloc(100);
double a=1,b,c;
char ac;
scanf("%s",str);
sscanf(str,"%lf%c%lf=%lf",&a,&ac,&b,&c);
//printf("%d%c%d=%d",a,ac,b,c);
call(a,b,c,ac);
//if(result)
    return 0;
}