Update cv4/a_train.c

cv4/a_train.c

@@ -3,6 +3,7 @@
 
 
 
+
 struct car* add_car(struct car* first,const char* target)
 {
     struct car* ret=first;
@@ -29,7 +30,6 @@ void print_train(struct car* first)
 {
     if(first==NULL)
     {
-        
         return;
     }
 
@@ -39,7 +39,6 @@ void print_train(struct car* first)
         first=first->next;
         if(first) printf("->");
     }while(first!=NULL);
-
 }
 
 void cancel_train(struct car* first)
@@ -62,38 +61,37 @@ struct car* clear_train(struct car* first, const char* target)
     {
         return first;
     }
-   
+
+    
     while(strcmp(first->value, target)==0) 
     {
         t=first;
         first=first->next;
         free(t);
-        
+      
         if(first==NULL)
         {
-            
+        
            return NULL;
         }        
     }
 
-      
-    ptr=first;
    
-    do
+    ptr=first;
+
+    while (ptr->next != NULL)
     {
-        if(strcmp(ptr->next->value, target)==0)
+        if (strcmp(ptr->next->value, target) == 0)
         {
-            t=ptr->next;;
-            ptr->next = ptr -> next->next;
+            t = ptr->next;
+            ptr->next = ptr->next->next;
             free(t);
         }
         else
         {
-            ptr = ptr -> next;
+            ptr = ptr->next;
         }
-    }while(ptr->next);
-
+    }
 
 	return first;
 }
-