diff --git a/du4/program b/du4/program
index bbcaec8..e5fc2da 100755
Binary files a/du4/program and b/du4/program differ
diff --git a/du4/program.c b/du4/program.c
index ecaa58b..cfb85f3 100644
--- a/du4/program.c
+++ b/du4/program.c
@@ -5,14 +5,12 @@
 #include <ctype.h>
 
 
-
-int main(){
-
-       int i,j; 
+int main() {
+        int i,j; 
        double number1, number2, summary,msum; 
        char operand, equ; 
        float rsum=0;
-/*       char input[1000];
+       /*       char input[1000];
        char num_str[30] = {0};
        float numbers[3];
        fgets(input, 999, stdin);
@@ -39,7 +37,7 @@ int main(){
 */ 
     char* input = calloc(1000, 1);
     while (1) {
-       
+        
         input = fgets(input, 1000, stdin);
         if (input == NULL) break;
  
@@ -47,9 +45,9 @@ int main(){
         if (input[0] == '\n' || input[0] == EOF || strlen(input) <= 0)
             break;
  
-        float values[3] = {0};
+        float values[3] = {0}; 
         char operation = 0;    
-        
+
         int k = 0; 
         int num = strlen(input);
         for (int i = 0; i < num; i++) {
@@ -60,7 +58,7 @@ int main(){
             if (isalpha(input[i]))
                 break;
  
-            
+          
             if (i < strlen(input) && (isdigit(input[i]) || input[i] == '.' || (input[i] == '-' && isdigit(input[i + 1])))) {
                 char temp[100] = {0}; 
                 for (int j = 0; i < strlen(input) && (isdigit(input[i]) || input[i] == '.' || input[i] == '-'); j++) {
@@ -75,85 +73,115 @@ int main(){
             }
         }
  
-        
+       
         if (k != 3) {
             printf("CHYBA\n");
             continue;
         }
  
-        
         if (operation == 0 && values[1] < 0) {
             operation = '-';
             values[1] = abs(values[1]); 
         }
  
-       
-        float result = 0;     
-      
-      
-      
-////////////////////////////////////////////////  
-      
-          /*if((operand == '/') && (number2 == 0)){
+        
+        float result = 0;
+ 
+        switch (operation) {
+        case '+': {
+            result = values[0] + values[1];
+            break;
+        }
+        case '-': {
+            result = values[0] - values[1];
+            break;
+        }
+        case '/': {
+            result = values[0] / values[1];
+            break;
+        }
+        case '*': {
+            result = values[0] * values[1];
+            break;
+        }
+        default: {
+            printf("CHYBA\n");
+            continue;
+        }
+        }
+ 
+        
+        char result_string[50];
+        sprintf(result_string, "%.2f", result);
+        result = atof(result_string);
+ 
+        if (result == values[2])
+            printf("OK\n");
+        else
+            printf("ZLE\n");
+    }
+     if((operand == '/') && (number2 == 0)){
                 printf("Nulou sa nedá deliť");
           }
           if(operand !='+' && operand !='-' && operand !='*' && operand !='/'){
               return 1;
               printf("\n");  
           }                         
-          */
-          msum=values[2];
-          if(operation=='+'){
-                        rsum=values[0]+values[1];
+          
+          //msum=values[2];
+          if(operand=='+'){
+            //            rsum=values[0]+values[1];
                         char rmsum[50];
                         sprintf(rmsum, "%.2f", msum);
                         msum = atof(rmsum);                        
                         if(msum==rsum){
-                          printf("OK\n");
+                          //printf("OK\n");
                         }
                         else{
-                          printf("ZLE\n");
+                          //printf("ZLE\n");
                         }
                         //printf("%lf\n",rsum);
           } 
-          else if(operation=='-'){
-                        rsum=values[0]-values[1];
+          else if(operand=='-'){
+              //          rsum=values[0]-values[1];
                         char rmsum[50];
                         sprintf(rmsum, "%.2f", msum);
                         msum = atof(rmsum);
                         if(msum==rsum){
-                          printf("OK\n");
+                          //printf("OK\n");
                         }
                         else{
-                          printf("ZLE\n");
+                          //printf("ZLE\n");
                         }
                         //printf("%lf\n",rsum);
           }
-          else if(operation=='*'){
-                        rsum=values[0]*values[1];
+          else if(operand=='*'){
+                //        rsum=values[0]*values[1];
                         char rmsum[50];
                         sprintf(rmsum, "%.2f", msum);
                         msum = atof(rmsum);
                         if(msum==rsum){
-                          printf("OK\n");
+                          //printf("OK\n");
                         }
                         else{
-                          printf("ZLE\n");
+                          //printf("ZLE\n");
                         }
                         //printf("%lf\n",rsum); 
           }
-          else if(operation=='/'){
-                        rsum=values[0]/values[1];
+          else if(operand=='/'){
+                  //      rsum=values[0]/values[1];
                         char rmsum[50];
                         sprintf(rmsum, "%.2f", msum);
                         msum = atof(rmsum);
                         if(msum==rsum){
-                          printf("OK\n");
+                          //printf("OK\n");
                         }
                         else{
-                          printf("ZLE\n");
+                          //printf("ZLE\n");
                         }
                         //printf("%lf\n",rsum);
           }
-          }
-          }  
\ No newline at end of file
+    free(input);
+ 
+    return 0;
+}