build

docs/chapter_array_and_linkedlist/linked_list.md

@@ -777,9 +777,6 @@ comments: true
     /* 删除链表的节点 n0 之后的首个节点 */
     #[allow(non_snake_case)]
     pub fn remove<T>(n0: &Rc<RefCell<ListNode<T>>>) {
-        if n0.borrow().next.is_none() {
-            return;
-        };
         // n0 -> P -> n1
         let P = n0.borrow_mut().next.take();
         if let Some(node) = P {
@@ -988,15 +985,23 @@ comments: true
 
     ```rust title="linked_list.rs"
     /* 访问链表中索引为 index 的节点 */
-    pub fn access<T>(head: Rc<RefCell<ListNode<T>>>, index: i32) -> Rc<RefCell<ListNode<T>>> {
-        if index <= 0 {
-            return head;
-        };
-        if let Some(node) = &head.borrow().next {
-            return access(node.clone(), index - 1);
+    pub fn access<T>(head: Rc<RefCell<ListNode<T>>>, index: i32) -> Option<Rc<RefCell<ListNode<T>>>> {
+        fn dfs<T>(
+            head: Option<&Rc<RefCell<ListNode<T>>>>,
+            index: i32,
+        ) -> Option<Rc<RefCell<ListNode<T>>>> {
+            if index <= 0 {
+                return head.cloned();
+            }
+
+            if let Some(node) = head {
+                dfs(node.borrow().next.as_ref(), index - 1)
+            } else {
+                None
+            }
         }
 
-        return head;
+        dfs(Some(head).as_ref(), index)
     }
     ```
 
@@ -1219,14 +1224,19 @@ comments: true
 
     ```rust title="linked_list.rs"
     /* 在链表中查找值为 target 的首个节点 */
-    pub fn find<T: PartialEq>(head: Rc<RefCell<ListNode<T>>>, target: T, index: i32) -> i32 {
-        if head.borrow().val == target {
-            return index;
-        };
-        if let Some(node) = &head.borrow_mut().next {
-            return find(node.clone(), target, index + 1);
+    pub fn find<T: PartialEq>(head: Rc<RefCell<ListNode<T>>>, target: T) -> i32 {
+        fn find<T: PartialEq>(head: Option<&Rc<RefCell<ListNode<T>>>>, target: T, idx: i32) -> i32 {
+            if let Some(node) = head {
+                if node.borrow().val == target {
+                    return idx;
+                }
+                return find(node.borrow().next.as_ref(), target, idx + 1);
+            } else {
+                -1
+            }
         }
-        return -1;
+
+        find(Some(head).as_ref(), target, 0)
     }
     ```