Update cv7/program.c

cv7/program.c

@@ -8,7 +8,7 @@
 
 struct tree
 {
-  
+
   char value[SIZE];
   
   struct tree *left, *right;
@@ -18,20 +18,24 @@ struct tree* read_tree()
 {
     char buffer[SIZE];
     memset(buffer,0,SIZE);
-    char* r = fgets(buffer,SIZE,stdin);
-   
+    char* r = fgets(buffer,SIZE,stdin);    
+        
+  
     assert(r);
+
+    if(buffer[0]=='\n')
+        return NULL;
     struct tree* node = (struct tree*)calloc(1,sizeof(struct tree));
     memcpy(node->value,buffer,SIZE);
-   
+  
     node->left=NULL;
     node->right=NULL;
 
     if(node->value[0]!='*')
     {
-        
+       
         node->left=read_tree(node->left);
-    
+ 
         node->right=read_tree(node->right);
     }
     return node;
@@ -42,7 +46,7 @@ void print_tree(struct tree* tree,int offset){
     for (int i = 0; i < offset; i++){
         printf(".");
     }
-  
+
     if(tree)
         printf("%s",tree->value);
     if (tree->left){
@@ -53,6 +57,13 @@ void print_tree(struct tree* tree,int offset){
     }
 }
 
+void destroy_tree(struct tree* tree){
+    if(tree==NULL) return;
+
+    destroy_tree(tree->left);
+    destroy_tree(tree->right);
+    free(tree);
+}
 
 int main(void)
 {
@@ -82,11 +93,10 @@ int main(void)
         }while(1);
         
     }while(1);
-    
-    
+  
     printf("Koniec\n");
+    destroy_tree(tr);
+    tr=NULL;
 
   return 0;
 }
-
-