def construcrt_list(self, s: str):
prev_node = None
for digit in s:
num = int(digit)
node = ListNode(num, prev_node)
prev_node = node
return prev_node
def reverseList(self, head: ListNode) -> ListNode:
new_head = None
current = head
while True:
if not current:
break
new_head = ListNode(current.val, new_head)
current = current.next
return new_head
def swapPairs(self, head: ListNode) -> ListNode:
if not head:
return head
next = head.next
if not next:
return head
rest = next.next
next.next = head
head.next = self.swapPairs(rest)
return next
def list_partition(node: ListNode, value: int) -> ListNode:
less = None
bigger = None
while node:
next = node.next
if node.val < value:
node.next = less
less = node
else:
node.next = bigger
bigger = node
node = next
if not less:
return bigger
head = less
while less.next:
less = less.next
less.next = bigger
return head
def run():
lists = [
ListNode(1, ListNode(2, ListNode(3, ListNode(4, ListNode(5, ListNode(6)))))),
#ListNode(5, ListNode(2, ListNode(3, ListNode(4, ListNode(1))))),
#ListNode(1, ListNode(2, ListNode(3, ListNode(3, ListNode(2, ListNode(1)))))),
#ListNode(1, ListNode(1)),
]
for l in lists:
print(Solution.list_partition(l, 3))
class Solution:
def removeElement(self, head: ListNode, n: int) -> ListNode:
previous = None
current = head
if head.val == n:
return head.next
while current:
if current.val == n:
previous.next = current.next
break
previous = current
current = current.next
return head
s = Solution()
a5 = ListNode(5)
a4 = ListNode(4, a5)
a3 = ListNode(3, a4)
a2 = ListNode(2, a3)
a1 = ListNode(1, a2)
b1 = ListNode(1)
print(s.removeElement(b1, 1))
def reverseNode(self, current, new):
if not current:
return new
new = ListNode(current.val, new)
return self.reverseNode(current.next, new)
break
return res
def reversed_num(self, s: str):
reversed = s[::-1]
return int(reversed)
def construcrt_list(self, s: str):
prev_node = None
for digit in s:
num = int(digit)
node = ListNode(num, prev_node)
prev_node = node
return prev_node
solution = Solution()
a1 = ListNode(3)
a2 = ListNode(4, a1)
a3 = ListNode(2, a2)
b1 = ListNode(4)
b2 = ListNode(6, b1)
b3 = ListNode(5, b2)
# 7, 0, 8
print(solution.addTwoNumbers(a3, b3))
def run():
test_cases = [
ListNode(
1,
ListNode(2, ListNode(3, ListNode(4, ListNode(5,
ListNode(6)))))),
ListNode(1, ListNode(2, ListNode(3, ListNode(4, ListNode(5))))),
ListNode(
1,
ListNode(2, ListNode(3, ListNode(3, ListNode(2,
ListNode(1)))))),
ListNode(1, ListNode(1)),
]
for test_case in test_cases:
print(Solution.is_palyndrome(test_case))
# https://leetcode.com/problems/swap-nodes-in-pairs/
from tasks.utils.list_node import ListNode
class Solution:
def swapPairs(self, head: ListNode) -> ListNode:
if not head:
return head
next = head.next
if not next:
return head
rest = next.next
next.next = head
head.next = self.swapPairs(rest)
return next
n8 = ListNode(8)
n7 = ListNode(7, n8)
n6 = ListNode(6, n7)
n5 = ListNode(5, n6)
n4 = ListNode(4, n5)
n3 = ListNode(3, n4)
n2 = ListNode(2, n3)
n1 = ListNode(1, n2)
s = Solution()
print(s.swapPairs(n1))
for i in range(len(heads)):
if heads[i].val < current_min:
target_i = i
current_min = heads[i].val
target = heads[target_i]
if head is None:
head = target
cur = head
else:
cur.next = target
cur = target
if target.next:
heads[target_i] = target.next
else:
heads.pop(target_i)
return head
s = Solution()
print(
s.mergeKLists([
ListNode(50, ListNode(60, ListNode(70))),
ListNode(1, ListNode(4, ListNode(6))),
ListNode(2, ListNode(88, ListNode(101))),
]))
print(s.mergeKLists([]))
print(s.mergeKLists([None, None]))