# Input: head = [1]
# Output: 1
#
# Example 4:
# Input: head = [1, 0, 0, 1, 0, 0, 1, 1, 1, 0, 0, 0, 0, 0, 0]
# Output: 18880
#
# Example 5:
# Input: head = [0, 0]
# Output: 0
#
# Constraints:
# The Linked List is not empty.
# Number of nodes will not exceed 30.
# Each node 's value is either 0 or 1.
from LinkedListx import linked_list
def get_decimal_value(head):
num = head.val
print(num)
while head.next:
num = num * 2 + head.next.val
print(num)
head = head.next
return num
list1 = linked_list([1, 1, 1, 1])
print(get_decimal_value(list1))
#
# The number of nodes in the list is n.
# 1 <= k <= n <= 105
# 0 <= Node.val <= 100
from LinkedListx import linked_list
def swap_nodes(head, k):
curr = head
knode2 = head
for _ in range(k - 1):
curr = curr.next
knode1 = curr
while curr.next is not None:
curr = curr.next
knode2 = knode2.next
knode1.val, knode2.val = knode2.val, knode1.val
return head
list1 = linked_list([1, 2, 3, 4, 5])
print(list1)
print(swap_nodes(list1, 2))
list1 = linked_list([1])
print(list1)
print(swap_nodes(list1, 1))
def swap_pairs(head):
if head is None:
return None
if head.next is None:
return head
curr = head
while True:
curr.val, curr.next.val = curr.next.val, curr.val
if curr.next.next is None or curr.next.next.next is None:
break
curr = curr.next.next
return head
list1 = linked_list([1])
print(list1)
print(swap_pairs(list1))
list1 = linked_list([1, 2])
print(list1)
print(swap_pairs(list1))
list1 = linked_list([1, 2, 3])
print(list1)
print(swap_pairs(list1))
list1 = linked_list([1, 2, 3, 4])
print(list1)
print(swap_pairs(list1))
# continue # prev = curr # curr = curr.next # # return head # list1 = linked_list([1, 4, 3, 2, 5, 2]) # print(list1) # print(partition(list1, 3)) # list1 = linked_list([2, 1]) # print(list1) # print(partition(list1, 2)) # list1 = linked_list([1, 1]) # print(list1) # print(partition(list1, 0)) list1 = linked_list([5, 4, 3, 2, 1]) print(list1) print(partition(list1, 3)) list1 = linked_list([5]) print(list1) print(partition(list1, 3)) list1 = linked_list([]) print(list1) print(partition(list1, 3))
# return head # class Solution: # def oddEvenList(self, head: ListNode) -> ListNode: # cur = head # values = [] # while cur: # values.append(cur.val) # cur = cur.next # # i = 0 # cur = head # while i < len(values): # cur.val = values[i] # cur = cur.next # i += 2 # i = 1 # while i < len(values): # cur.val = values[i] # cur = cur.next # i += 2 # return head # 1 2 3 4 5 # 1 3 2 4 5 move 2 to 1 # 1 3 5 2 4 move 4 to 2 list1 = linked_list([1, 2, 3, 4, 5, 6, 7]) print(list1) print(odd_even_list(list1))
# while curr:
# nodes.append(curr.val)
# curr = curr.next
#
# curr = head
# while curr:
# if curr.val != nodes.pop():
# return False
# curr = curr.next
#
# return True
def is_palindrome(head):
arr = []
curr = head
while curr:
arr.append(curr.val)
curr = curr.next
n = len(arr)
for i in range(n // 2):
if arr[i] != arr[n - 1 - i]:
return False
return True
list1 = linked_list([1, 2, 3, 2, 1])
print_list(list1)
print(is_palindrome(list1))
def print_list(curr):
while curr:
print(curr.val, end=' ')
curr = curr.next
print('')
def get_intersection_node(heada, headb):
seta = set()
curr = heada
while curr:
seta.add(curr)
curr = curr.next
curr = headb
while curr:
if curr in seta:
return curr
curr = curr.next
return None
list1 = linked_list([1, 2, 6, 7, 8])
print(list1)
list2 = linked_list([3, 4, 5])
list2.next.next.next = list1.next.next
print(list2)
print((get_intersection_node(list1, list2)))
while curr:
print(curr.val, end=' ')
curr = curr.next
def get_list_value(head):
list_val = 0
i = 0
curr = head
while curr:
list_val += curr.val * 10**i
i += 1
curr = curr.next
return list_val
def add_two_numbers(l1, l2):
sumx = get_list_value(l1) + get_list_value(l2)
node_vals = [int(d) for d in reversed(str(sumx))]
head = prev = ListNode(node_vals[0])
for val in node_vals[1:]:
prev.next = ListNode(val)
prev = prev.next
return head
list1 = linked_list([2, 4, 3])
list2 = linked_list([5, 6, 4])
print_list(add_two_numbers(list1, list2))
# else: # head = curr2 # # while curr1 and curr2: # next1 = curr1.next # next2 = curr2.next # if curr1.val < curr2.val: # curr1.next = curr2 # else: # curr2.next = curr1 # # if next1 is None: # tail1 = curr1 # if next2 is None: # tail2 = curr2 # # curr1 = next1 # curr2 = next2 # # if curr1: # tail2.next = curr1 # # if curr2: # tail1.next = curr2 # # return head list1 = linked_list([3, 5]) list2 = linked_list([1, 2, 4]) print_list(merge_two_lists(list1, list2))
# class Solution: # def removeElements(self, head, val): # """ # :type head: ListNode # :type val: int # :rtype: ListNode # """ # # dummy_head = ListNode(-1) # dummy_head.next = head # # current_node = dummy_head # while current_node.next != None: # if current_node.next.val == val: # current_node.next = current_node.next.next # else: # current_node = current_node.next # # return dummy_head.next # list1 = linked_list([6, 6, 6, 6, 6, 1, 2, 6, 3, 4, 5, 6]) list1 = linked_list([1, 2, 6, 3, 4, 5, 6]) print(list1) print(remove_elements(list1, 6)) list1 = linked_list([1, 2, 2, 1]) print(list1) print(remove_elements(list1, 2))