double_num_represent_ll.py (800B)
| # 2816. Double a Number Represented as a Linked List
"""
given the 'head' of a non-empty linked list representing a non negative
integer without leading zeros. return the 'head' of the linked list after
doubling it.
"""
# Definition for singly-linked list.
class ListNode(object):
def __init__(self, val=0, next=None):
self.val = val
self.next = next
class Solution(object):
def doubleIt(self, head):
"""
:type head: Optional[ListNode]
:rtype: Optional[ListNode]
"""
if head.val > 4:
head = ListNode(0, head)
node = head
while node:
node.val = (node.val * 2) % 10
if node.next and node.next.val > 4:
node.val += 1
node = node.next
return head
|
