#include <stdio.h>
#include<string.h>
#include<math.h>
#include<stdlib.h>
char* compactString(char *src,int leng) {
    char *new_str = (char*)calloc(leng+1,sizeof(char));
    int k=0;
    for(int i=0;i<leng;i++){
        if(src[i]!=' '){
            new_str[k] = src[i];
            k++;
        }
    }
    return new_str;
}



double operation(double first,double second,char c){
    double x =0;
    if(c=='*'){
         x=first*second;
        return x;
    }
    else if(c =='-'){
         x=first-second;
        return x;
    }
    else if(c=='/'){
         x=first/second;
        return x;
    }
    x= first+second;
    return x;
}


double round_to(double value, double eps)
{

  return floor(value/eps + 0.5) * eps;
}

double compare_percent(double a, double b, double eps)
{
  double diff = round_to( (a - b) * 2 / (a + b), eps);
  return diff < 0 ? -1 : diff > 0 ? +1 : 0;
}

int check(char *str){
    int flag=0;
    char symb[5]="*-+/=";
    for(int i =0;i<strlen(str);i++){
        for(int k =0;k<5;k++){
            for(int j =0;j<5;j++){
                if(str[i]==symb[j]&&str[i+1]==symb[k]){
                    return 0;
                }
            }
        }
        if(str[i]=='='){
            flag=1;
        }
        if((str[i]>='a'&&str[i]<='z')||(str[i]>='A'&&str[i]<='Z')){
            return 0;
        }
    }
    return flag==1?1:0;
}


int main()
{
    char str[100][100];
  	for(int i =0;fgets(str[i],100,stdin);i++){
  	    if(str[i][0]=='\n'){
  	        break;
  	    }
    	char *new_str = compactString(str[i],strlen(str[i]));
    	double first =-5,second =-5,res=-5;
    	char c='E';
    	sscanf(new_str,"%lf%c%lf%*[=]%lf",&first,&c,&second,&res);
    
    
    	if(c!=43&&c!=42&&c!=45&&c!=47||check(new_str)==0){
    	    printf("CHYBA\n");
          	continue;
    	}
    	double my_res = operation(first,second,c);
    	if(compare_percent(res,my_res,0.01)==0){
    	    printf("OK\n");
    	}
    	else{
    	    printf("ZLE\n");
   	    }
    
}

    return 0;
}