Given the `head`

of a sorted linked list, *delete all duplicates such that each element appears only once*. Return *the linked list **sorted** as well*.

**Example 1:**

**Input:** head = [1,1,2]

**Output:** [1,2]

**Example 2:**

**Input:** head = [1,1,2,3,3]

**Output:** [1,2,3]

**Constraints:**

- The number of nodes in the list is in the range
`[0, 300]`

. `-100 <= Node.val <= 100`

- The list is guaranteed to be
**sorted**in ascending order.

Solution: