#21: description update

Author: vetalapo

c-sharp/Problems/linked-list/MergeTwoSortedLists.cs

@@ -3,13 +3,29 @@
  * Merge Two Sorted Lists 
  **
  * You are given the heads of two sorted linked lists list1 and list2.
- *
  * Merge the two lists into one sorted list.
  * The list should be made by splicing together the nodes of the first two lists.
  *
  * Return the head of the merged linked list.
  *
  * Both list1 and list2 are sorted in non-decreasing order.
+ *
+ * Example 1:
+ *   Input: list1 = [1,2,4], list2 = [1,3,4]
+ *   Output: [1,1,2,3,4,4]
+ *
+ * Example 2:
+ *   Input: list1 = [], list2 = []
+ *   Output: []
+ *
+ * Example 3:
+ *   Input: list1 = [], list2 = [0]
+ *   Output: [0]
+ *
+ * Constraints:
+ *   •  The number of nodes in both lists is in the range [0, 50].
+ *   •  -100 <= Node.val <= 100
+ *   •  Both list1 and list2 are sorted in non-decreasing order.
  **
  * https://leetcode.com/problems/merge-two-sorted-lists/
 ***/