Remove Duplicates from Sorted List II · LeetCode Site Generator

Description

Given 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.

Example 1:

Input: 1->2->3->3->4->4->5
Output: 1->2->5

Example 2:

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

Solution(javascript)


const deleteDuplicates = function (head) {
  const temp = {
    next: head,
  }
  let prev = temp
  let current = head
  while (current) {
    let isDuplicate = false
    while (current.next && current.val === current.next.val) {
      isDuplicate = true
      current.next = current.next.next
    }
    current = current.next
    if (isDuplicate) {
      prev.next = current
      isDuplicate = false
    } else {
      prev = prev.next
    }
  }
  return temp.next
}