clear

cv5/a_train.c

@@ -62,23 +62,33 @@ struct car* clear_train(struct car* first, const char* target) {
             return first;
         }
     }
-    struct car* prev = first;
-    while(prev->next->next != NULL){
-        int x = strcmp(prev->next->value, target);
+    struct car* this = first;
+    while(this->next->next != NULL){
+        int x = strcmp(this->next->value, target);
         if(x == 0){ 
-            struct car* third = prev->next->next;
-            free(prev->next);
-            prev->next = third;
-            return prev;
+            struct car* curr = first;
+            struct car* prev = NULL;
+            if(first == this){
+                first = this->next;
+                free(this);
+                return first;
+            }
+            while(curr != this){
+                prev = curr;
+                curr = curr->next;
+            }
+            prev->next = curr->next;
+            this->next = NULL;
+            free(this);
         }
-        prev = prev->next;
+        this = this->next;
    }
 
 
-   int x = strcmp(prev->next->value, target);
+   int x = strcmp(this->next->value, target);
    if(x == 0){
-       free(prev->next);
-       prev->next = NULL;
+       free(this->next);
+       this->next = NULL;
        return first;
    }
    return first;