题解 | 序列链表化

# class ListNode:
#     def __init__(self, x):
#         self.val = x
#         self.next = None
#
# 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
# @param arr int整型一维数组 
# @return ListNode类
#
class Solution:
    def vectorToListnode(self , arr: List[int]) -> ListNode:
        # write code here
        prev  = ListNode(0) #创建头结点
        res = prev      
        #res指针记录头结点不改动，prev、cur两个指针同时向后移动用于生成单链表
        for a in arr :
            cur = ListNode(a)
            prev.next = cur
            prev = cur

        return res.next