feat: add swift implementation to lcof2 problem: No.029 (#3028)

Author: klever34

lcof2/剑指 Offer II 029. 排序的循环链表/README.md

@@ -274,6 +274,51 @@ function insert(head: Node | null, insertVal: number): Node | null {
 }
 ```
 
+#### Swift
+
+```swift
+/* class Node {
+*     var val: Int
+*     var next: Node?
+
+*     init(_ val: Int) {
+*         self.val = val
+*         self.next = nil
+*     }
+* }
+*/
+
+class Solution {
+    func insert(_ head: Node?, _ insertVal: Int) -> Node? {
+        let newNode = Node(insertVal)
+        if head == nil {
+            newNode.next = newNode
+            return newNode
+        }
+
+        var current = head
+        repeat {
+            if current!.val <= insertVal && insertVal <= current!.next!.val {
+                break
+            }
+
+            if current!.val > current!.next!.val && (insertVal >= current!.val || insertVal <= current!.next!.val) {
+                break
+            }
+
+            if current!.next === head {
+                break
+            }
+            current = current!.next
+        } while current !== head
+
+        newNode.next = current!.next
+        current!.next = newNode
+        return head
+    }
+}
+```
+
 <!-- tabs:end -->
 
 <!-- solution:end -->

lcof2/剑指 Offer II 029. 排序的循环链表/Solution.swift

@@ -0,0 +1,40 @@
+/* class Node {
+*     var val: Int
+*     var next: Node?
+
+*     init(_ val: Int) {
+*         self.val = val
+*         self.next = nil
+*     }
+* }
+*/
+
+class Solution {
+    func insert(_ head: Node?, _ insertVal: Int) -> Node? {
+        let newNode = Node(insertVal)
+        if head == nil {
+            newNode.next = newNode
+            return newNode
+        }
+        
+        var current = head
+        repeat {
+            if current!.val <= insertVal && insertVal <= current!.next!.val {
+                break
+            }
+
+            if current!.val > current!.next!.val && (insertVal >= current!.val || insertVal <= current!.next!.val) {
+                break
+            }
+
+            if current!.next === head {
+                break
+            }
+            current = current!.next
+        } while current !== head
+
+        newNode.next = current!.next
+        current!.next = newNode
+        return head
+    }
+}