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

int call(float A, float B, float C, char AC){
    if(AC=='/'&&B==0||AC==('+'||'-'||'*'||'-')){
        return printf("CHYBA\n");
    }
    else if(AC=='+'){
        if(A+B==C)return printf("OK\n");
        return printf("ZLE\n");
    }
    else if(AC=='-'){
        if(A-B==C)return printf("OK\n");
        return printf("ZLE\n");
    }
    else if(AC=='*'){
        if(A*B==C)return printf("OK\n");
        return printf("ZLE\n");
    }
    if(AC=='/'){
        float Cc=A/B;
        Cc=(int)(Cc*100000);
        Cc=(float)Cc/100000;
        if(Cc==C)return printf("OK\n");
        printf("%f",Cc);
        return printf("ZLE\n");
    }
    return printf("CHYBA");
}
int main()
{
char *str;
str=(char*)malloc(100);
float a,b,c;
char ac,el;
int ind=0;
for(int i=0;el!='\n';i++){
    el=getchar();
    if(isspace(el)){
        continue;
    }
    str[ind]=el;
    ind++;
}
sscanf(str,"%f%c%f=%f ",&a,&ac,&b,&c);
call(a,b,c,ac);
    return 0;
}