def deleteMax(head):
head = reverse(head)
printlist(head)
maxval = -1*maxint
curr = head
prev = None
while curr is not None and curr.next is not None:
if curr.next.data < maxval:
temp = curr.next
curr.next = temp.next
del temp
else:
curr = curr.next
maxval = max(maxval, curr.data)
head = reverse(head)
return head
def sort(head):
first_half = head
while first_half.next is not None:
if first_half.data > first_half.next.data:
break
first_half = first_half.next
second_half = first_half.next
first_half.next = None
second_half.prev = None
first_half = head
printlist(first_half)
printlist(second_half)
second_half = reverse(second_half)
printlist(second_half)
return merge(first_half, second_half)
node_a.data, node_b.data = node_b.data, node_a.data
def zigzagorder(head):
flag = True
curr = head
while curr.next is not None:
if flag and curr.data > curr.next.data:
swap(curr, curr.next)
if not flag and curr.data < curr.next.data:
swap(curr, curr.next)
flag = not flag
curr = curr.next
return head
if __name__ == "__main__":
res = []
start = time.time()
for _ in xrange(1):
size = random.randint(10, 15)
nums = [random.randint(0, 100) for _ in xrange(size)]
head = mklist(nums)
printlist(head)
head = zigzagorder(head)
printlist(head)
def cutHalf(head):
slowptr = head
fastptr = head
while fastptr.next != head and fastptr.next.next != head:
slowptr = slowptr.next
fastptr = fastptr.next.next
if fastptr.next.next == head:
fastptr = fastptr.next
firsthead = slowptr.next
slowptr.next = None
fastptr.next = None
return head, firsthead
if __name__ == "__main__":
head = tail = Node(10, None)
for i in xrange(9, -1, -1):
head = Node(i, head)
tail.next = head
printlist(head)
head1, head2 = cutHalf(head)
printlist(head1)
printlist(head2)
def reverse(head):
prev = None
curr = head
while curr is not None:
next = curr.next
curr.next = prev
curr.prev = next
prev = curr
curr = next
return prev
if __name__ == "__main__":
prev = None
head = None
for i in xrange(10, 0, -1):
head = Node(i, prev, head)
if prev is not None:
prev.prev = head
prev = head
head.prev = None
tail = printlist(head)
head = reverse(head)
printlist(head)
two = two.next
return one is None and two is None
if __name__ == "__main__":
head_one = Node(0, None)
for i in xrange(1,10):
node = Node(i, head_one)
head_one = node
head_two = Node(0, None)
for i in xrange(1,10):
node = Node(i, head_two)
head_two = node
head_three = Node(0, None)
for i in xrange(1,5):
node = Node(i, head_three)
head_three = node
for i in xrange(1,5):
node = Node(randint(1,100), head_three)
head_three = node
printlist(head_one)
printlist(head_two)
print("\nIs identical Itr, ", isIdenticalItr(head_one, head_two))
print("\nIs identical Rec, ", isIdenticalRec(head_one, head_two))
print("\nIs identical Itr, ", isIdenticalItr(head_one, head_three))
print("\nIs identical Rec, ", isIdenticalRec(head_one, head_three))
