2021年6月3日

24 . 两两交换链表中的结点

给定一个链表，两两交换其中相邻的结点，返回头结点

class Solution:
	def swapPairs(self, head: ListNode) -> ListNode:
		dummyHead = ListNode(0)
		dummyHead.next = head
		temp = dummyHead
		while temp.next and temp.next.next:
			node1 = temp.next
			node2 = temp.next.next
			temp.next = node2
			node1.next = node2.next
			node2.next = node1
			temp = node1
		return dummyHead.next

时间复杂度:O(n)
空间复杂度:O(1)

26 . 删除有序数组中的重复元素

给定一个有序数组nums，原地删除重复出现的元素

class Solution:
	def removeDuplicates(self, nums: List[int]) -> int:
		count = 0
		slow = 0
		fast = 1
		while fast < len(nums):
			if nums[fast] != nums[slow]:
				slow += 1
				nums[slow] = nums[fast]
			fast += 1
		return slow + 1