小黑leetcode之旅,然后要和学长吃串串香啦:876. 链表的中间结点

小黑做法1

# Definition for singly-linked list.
# class ListNode:
#     def __init__(self, val=0, next=None):
#         self.val = val
#         self.next = next
class Solution:
    def middleNode(self, head: ListNode) -> ListNode:
        arr = []
        while head:
            arr.append(head)
            head = head.next
        if len(arr) % 2:
            index = int(len(arr) / 2)
        else:
            index = int((len(arr)+0.5)/2)
        return arr[index]
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小黑做法2

# Definition for singly-linked list.
# class ListNode:
#     def __init__(self, val=0, next=None):
#         self.val = val
#         self.next = next
class Solution:
    def middleNode(self, head: ListNode) -> ListNode:
        length = 0
        node = head
        while node:
            length += 1
            node = node.next
        node = head
        for i in range(length//2):
            node = node.next
        return node
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快慢指针法

# Definition for singly-linked list.
# class ListNode:
#     def __init__(self, val=0, next=None):
#         self.val = val
#         self.next = next
class Solution:
    def middleNode(self, head: ListNode) -> ListNode:
        harry_node = head
        slow_node = head
        while harry_node and harry_node.next:
            harry_node = harry_node.next.next
            slow_node = slow_node.next
        return slow_node
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小黑生活

祝贺舍友论文发表

找工作，难难难!!小黑也要加油!!!