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# 83. Remove Duplicates from Sorted List

<https://leetcode.com/problems/remove-duplicates-from-sorted-list>[/description/](https://leetcode.com/problems/climbing-stairs/description/)

Given a sorted linked list, delete all duplicates such that each element appear only *once*.

**Example 1:**

```
Input: 1->1->2
Output: 1->2
```

**Example 2:**

```
Input: 1->1->2->3->3
Output: 1->2->3
```

**Solution:**

```
# Definition for singly-linked list.
# class ListNode(object):
#     def __init__(self, x):
#         self.val = x
#         self.next = None

class Solution(object):
    def deleteDuplicates(self, head):
        """
        :type head: ListNode
        :rtype: ListNode
        """
        h = head
        while head and head.next:
            if head.val == head.next.val:
                head.next = head.next.next
            else:
                head = head.next
        return h
```