Merge pull request #2138 from solairerove/main

Create: 61-Rotate-List.py

Author: saip7795

python/0061-rotate-list.py

@@ -0,0 +1,26 @@
+class Solution:
+    def rotateRight(self, head: Optional[ListNode], k: int) -> Optional[ListNode]:
+        if not head or not head.next or k == 0:
+            return head
+
+        old_head = head
+
+        curr, size = head, 0
+        while curr:
+            curr, size = curr.next, size + 1
+
+        if k % size == 0:
+            return head
+
+        k %= size
+        slow = fast = head
+        while fast and fast.next:
+            if k <= 0:
+                slow = slow.next
+            fast = fast.next
+            k -= 1
+
+        new_tail, new_head, old_tail = slow, slow.next, fast
+        new_tail.next, old_tail.next = None, old_head
+
+        return new_head