#include <stdio.h>
#include <math.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
char array[100];
char array1[100];
char number1[100];
char number2[100];
char answer[100];
int p=0;
float zero=0;
char znak1;
char znak2;
float firstN=0;
float secondN=0;
float answer1=0;
float myAnswer=0;
char c;
char r;
char q;
int count = 0;
int scan(char* array2){
char* r = fgets(array1,100,stdin);
if (r == NULL){
        return -1;
}
        else{
        return 0;
        }
}
int main(){
scan(array1);
int i=0;
while(i<100){
        i=i+1;
        if(array1[i]!='\n'){
	        count=count+1;
	}	
        if(array1[i]=='\n'){	
	        if(array1[i+1]=='\n')
		{ 
		array1[i]='#';
		break;
		}
	}
        else
	{
	count=count+1;
	}
}
i=0;
int j=0;
int t=0;
while(array1[t]!='#'){
        array[p]=array1[t];
        if(array1[t]=='='){
	t=t+1;
	p=p+1;
	if(array1[t]==' '){
		array[p]=array1[t];
		t=t+1;
		p=p+1;
		}
	while(array1[t]!=' ')
		{
		if(array1[t]=='#'){
                        break;
                        }
		        array[p]=array1[t];
		        t=t+1;
		        p=p+1;
		        }
                while(array[i]!='\0'){
	                if(array[i]=='+'||array[i]=='-'||array[i]=='/'||array[i]=='*'){
	                        break;
	                }
	                else if(array[i]=='1'||array[i]=='2'||array[i]=='3'||array[i]=='4'||array[i]=='5'||array[i]=='6'||array[i]=='7'||array[i]=='8'||array[i]=='9'||array[i]=='0'||array[i]=='.'){
	                        number1[j]= array[i];
	                        i=i+1;
	                        j=j+1;
	                }
	                else if(array[i]==' ' || isalpha(array[i])){i++;}
	                        else{
	                        printf("CHYBA\n");
	                        return 0;
	                        }
                        }
                znak1=array[i];
                i=i+1;
                j=0;
                while(array[i]!='='){
                        if(array[i]=='1'||array[i]=='2'||array[i]=='3'||array[i]=='4'||array[i]=='5'||array[i]=='6'||array[i]=='7'||array[i]=='8'||array[i]=='9'||array[i]=='0'||array[i]=='.'){
                                number2[j]=array[i];
                                j=j+1;
	                        i=i+1;
                        }
	else if(array[i]==' '){
                i=i+1;
                }
        else{
                i=i+1;
                p=p+1;
        }
}
        znak2=array[i];
        i++;
        j=0;
        j=0;
while(array[i]=='1'||array[i]=='2'||array[i]=='3'||array[i]=='4'||array[i]=='5'||array[i]=='6'||array[i]=='7'||array[i]=='8'||array[i]=='9'||array[i]=='0'||array[i]==' '||array[i]=='.'){
        if(array[i]=='1'||array[i]=='2'||array[i]=='3'||array[i]=='4'||array[i]=='5'||array[i]=='6'||array[i]=='7'||array[i]=='8'||array[i]=='9'||array[i]=='0'||array[i]=='.'){
        answer[j]=array[i];
        i=i+1;
	j=j+1;
        }
	else if(array[i]==' '){
                i=i+1;
        }else{
                i=i+1;
                p=p+1;
                }
        }
        j=0;
        float firstN = atof(number1);
        float secondN = atof(number2); 
        float answer1 = atof(answer);
        if(znak1=='-'){
                myAnswer=firstN-secondN;
        }
        else if(znak1=='+'){
                myAnswer=firstN+secondN;
        }
        else if(znak1=='/'){
                myAnswer=firstN/secondN;
        }
        else if(znak1=='*'){
                myAnswer=firstN*secondN;
        }
                zero = myAnswer-answer1;
        if(zero>=-0.00001&&zero<=0.00001){
        printf("OK\n");
        }
        else{
                printf("ZLE\n");
        }
        i=0;
        p=-1; 
        memset(array,0,100);
        }
        p=p+1;
        t=t+1;
        scanf("\n%c",&q);
        if(c=='\n'){
        return 0;
        }
}
        return 0;
}