Merge remote-tracking branch 'origin/master'

LeetCodeSharp/Problems/Solution61.cs

@@ -0,0 +1,58 @@
+// [61] Rotate List
+
+using LeetCodeSharp.Utils;
+
+namespace LeetCodeSharp.Problems61
+{
+    // Submission codes start here
+
+    /**
+ * Definition for singly-linked list.
+ * public class ListNode {
+ *     public int val;
+ *     public ListNode next;
+ *     public ListNode(int val=0, ListNode next=null) {
+ *         this.val = val;
+ *         this.next = next;
+ *     }
+ * }
+ */
+    public class Solution
+    {
+        public ListNode RotateRight(ListNode head, int k)
+        {
+            // 排除链表为空/只有一个节点的情况
+            if (head?.next == null)
+            {
+                return head;
+            }
+
+            // 首先将链表连接为环形链表
+            var node = head;
+            var length = 1;
+
+            while (node.next != null)
+            {
+                node = node.next;
+                length += 1;
+            }
+
+            node.next = head;
+
+            var precursor = node;
+            var newHead = head;
+
+            for (var i = 0; i < length - k % length; i++)
+            {
+                newHead = newHead.next;
+                precursor = precursor.next;
+            }
+
+            // 断开环形链表
+            precursor.next = null;
+            return newHead;
+        }
+    }
+
+    // Submission codes end here
+}