Merge pull request #2230 from crazysamurai/add-problem

Create: 0061-rotate-list.java

Author: tahsintunan

java/0061-rotate-list.java

@@ -0,0 +1,31 @@
+//TC: O(n) + O(n- (n % k)) ~ O(n)
+//SC: O(1)
+
+class Solution {
+    public ListNode rotateRight(ListNode head, int k) {
+        if (head == null || head.next == null || k == 0)
+            return head;
+
+        int l = 1; // length of list
+        ListNode temp = head;
+
+        // calculate the list's length
+        while (temp.next != null) {
+            l++;
+            temp = temp.next;
+        }
+
+        temp.next = head; // make the list cyclic
+        k = k % l; // handles the case where k>l
+        k = l - k;
+
+        while (k > 0) {
+            temp = temp.next;
+            k--;
+        }
+        head = temp.next;
+        temp.next = null;
+
+        return head;
+    }
+}