增加 0203.移除链表元素 Rust版本

problems/0203.移除链表元素.md

@@ -358,6 +358,41 @@ func removeElements(head *ListNode, val int) *ListNode {
 }
 ```
 
+RUST:
+```rust
+// Definition for singly-linked list.
+// #[derive(PartialEq, Eq, Clone, Debug)]
+// pub struct ListNode {
+//   pub val: i32,
+//   pub next: Option<Box<ListNode>>
+// }
+// 
+// impl ListNode {
+//   #[inline]
+//   fn new(val: i32) -> Self {
+//     ListNode {
+//       next: None,
+//       val
+//     }
+//   }
+// }
+impl Solution {
+    pub fn remove_elements(head: Option<Box<ListNode>>, val: i32) -> Option<Box<ListNode>> {
+        let mut head = head;
+        let mut dummy_head = ListNode::new(0);
+        let mut cur = &mut dummy_head;
+        while let Some(mut node) = head {
+            head = std::mem::replace(&mut node.next, None);
+            if node.val != val {
+                cur.next = Some(node);
+                cur = cur.next.as_mut().unwrap();
+            }
+        }
+        dummy_head.next
+    }
+}
+```
+
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