题解 | 合并k个已排序的链表

#将全部元素都添加到list里进行sort，再构造链表返回

# 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 lists ListNode类一维数组 
# @return ListNode类
#
class Solution:
    def mergeKLists(self , lists: List[ListNode]) -> ListNode:
        # write code here
        if not lists:
            return None
        lt =[]
        for i in lists:
            l =[]
            p = i
            while p:
                l.append(p.val)
                p = p.next
            lt.extend(l)
        # print(lt)
        lt.sort()
        if not lt:
            return None
        ph= ListNode(lt[0])
        p = ph
        for j in range(1,len(lt)):
            tmp = ListNode(lt[j])
            p.next = tmp
            p = p.next
        return ph