Remove Duplicates from Sorted List II

IF
AlgoAxiomStaff Engineers
JSTS
Medium20 mins

Given the head of a sorted linked list, delete all nodes that have duplicate numbers, leaving only distinct numbers from the original list. Return the linked list sorted as well.

Examples

Example 1:

Input: head = [1,2,3,3,4,4,5]

Output: [1,2,5]

Explanation: Nodes with values 3 and 4 appear more than once, so all their occurrences are removed.

Example 2:

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

Output: [2,3]

Explanation: Node with value 1 appears three times, so all occurrences are removed.

Example 3:

Input: head = [1,1]

Output: []

Explanation: Both nodes have the same value, so the entire list is removed.

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
Source: Fast and Slow Pointers pattern — AlgoAxiom
JavaScript
Test Case 1
root = [1, 2, 3]
Test Case 2
root = [1, 2, 3, 4, 5]
Idle