def get_sublist(self, letter):
'''(PhoneBook, str) -> PhoneBook
Returns the phonebook of the contacts starting all contact names with
given string of letter from the phonebook of the alphabetical order
REQ: First Name or Surname must be given in the contact'''
# create an empty sll
sub = SingleLinkedList()
# traverse through the list to find the contact whose primary name
# start with the given string letter
curr = self._head
while (curr is not None):
# get the name of the contacts from the phonebook
new = curr.get_element().main_name()
# if the first letter of the contact name matches with letter given
if (str(new)[:1] == letter):
# create a node and add that node in sll
node = Node(curr.get_element())
sub.add_last(node)
# continue traversing
curr = curr.get_next()
else:
# else continue traversing
curr = curr.get_next()
# return the sll with given letter
return sub
def __init__(self, contact=None):
'''(PhoneBook, SingleLinkedList) -> NoneType
initializes the attributes of a phonebook
'''
# Representation Invariant (RI)
# PhoneBook contains contact(s) if it is not empty
SingleLinkedList.__init__(self)
# _size is non-negative
# add the first contact during initialization if provided
if contact is not None:
self.add(contact)
def rearrange_phonebook(self):
'''(PhoneBook) -> NoneType
Rearrages the phonebook in a way that brings all favourite contacts in
front of the book in alphabetical order following with all unfavourit
contacts from the phonebook that are present in the alphabetical order
REQ: List must be given'''
# Create an empty sll to store all favourite contacts
emp = SingleLinkedList()
# set prev to None to keep pointer of the previous node
prev = None
# set output to false
output = False
curr = self._head
# traverse through the phonebook to get all favourite contacts
while (curr is not None):
# check if thecontact is fav
if (curr.get_element().is_fav() is True):
# create a new node and add the contact in new sll created
new = Node(curr.get_element())
emp.add_last(new)
# if the element in head is fav, remove the node by moving
# pointer to the next node and setting it to head
if (prev is None):
self.set_head(self._head.get_next())
# remove the node but setting next to current node
else:
prev.set_next(curr.get_next())
# continue traversing through the list
curr = curr.get_next()
output = True
else:
# else continue traversing through the list
prev = curr
curr = curr.get_next()
# it there are favourite contacts present in the phonebook
if (output is True):
# use the helper method reverse, which changes the order of the
# the nodes in reversed order
rev_fav = self.reverse(emp)
# traverse through the list to add the favourites in the phonebook
# in front of the list
curr = rev_fav.get_head()
while (curr is not None):
# using the method of sll, add first; add the contacts up front
self.add_first(curr)
curr = curr.get_next()
def get_housemate(self, homephone):
'''(PhoneBook, str) -> PhoneBook
Returns the phonebook of the contacts whose homephones are same as
given homephone from the phonebook of the alphabetical order
REQ: homephone must be given in the contact'''
# Create an empty sll
home = SingleLinkedList()
# travrse through the list to get all the housemates who shares same hp
curr = self._head
while (curr is not None):
# get the housephone of each contact
new = curr.get_element().get_homephone()
# check if housephone of contact matches given contact
if (str(new) == homephone):
# create a node and add that in the given list
node = Node(curr.get_element())
home.add_last(node)
# continue traversing through the phonebook
curr = curr.get_next()
else:
# else continue through traversing the phonebook
curr = curr.get_next()
# return the phonebook with housemates sharing same housephone
return home
def toronto_phone(self):
'''(PhoneBook) -> (PhoneBook,PhoneBook)
Returns the phonebook of the contact starting with 416 and 647 in tuple
from the phonebook of the alphabetical order
REQ: Primary phone number must be given in the contact
REQ: the given contact must start with the 647 or 416 '''
# Create two empty linked list for storing different phone numbers
four_one_six = SingleLinkedList()
six_four_seven = SingleLinkedList()
# traverse through the list to add the phone numbers in the linked list
# according to their starting format
curr = self._head
while (curr is not None):
# get the primary phone number of the contact in the phonebook
new = curr.get_element().get_primaryphone()
# If the phine number starts with 647
if (str(new)[:3] == "647"):
# create the new node of the contact
node = Node(curr.get_element())
# add that contact in six_four_seven phonebook sll
six_four_seven.add_last(node)
# continue traversing through the list
curr = curr.get_next()
# If the phine number starts with 416
elif (str(new)[:3] == "416"):
# create the new node of the contact
node = Node(curr.get_element())
# add that contact in four_one_six phonebook sll
four_one_six.add_last(node)
# continue traversing through the list
curr = curr.get_next()
# if the format of primary phone number is not correct
else:
# raise an exception
raise InvalidFormatPhoneNumber("Invalid Format Phone Number")
# return the tuple with both the sll
return (four_one_six, six_four_seven)
def reverse(self, phoneb):
'''(PhoneBook,PhoneBook) -> PhoneBook
Reverse the contacts from the phonebook that are present in the
alphabetical order
REQ: List must be given'''
# create empty sll to return the reversed link
rev = SingleLinkedList()
# if the reversed sll is empty
if (rev.get_head() is None):
# create a node and set the element from given phonebook
new = Node(phoneb.get_head().get_element())
# set the node head
rev.set_head(new)
# Traverse through the given phonebook and continue traversing
# through the list
curr = phoneb._head.get_next()
while (curr is not None):
new = Node(curr.get_element())
rev.add_first(new)
curr = curr.get_next()
# return the reversed phonebook
return rev
def reversed_phonebook(self):
'''(PhoneBook) -> PhoneBook
Returns the phonebook of the contacts in the reverse order from the
phonebook of the alphabetical order
REQ: phonebook must not be empty'''
# create the empty sll for reverse contacts
rev = SingleLinkedList()
# if the reverse phonebook is empty
if (rev.get_head() is None):
# create a new node and add that element in reverse phonebook
new = Node(self.get_head().get_element())
# set that node as a head of the reverse phonebook
rev.set_head(new)
# traverse through the list & keep adding the contact in rev phonebook
curr = self._head.get_next()
while (curr is not None):
# create empty node and add the element in it
new = Node(curr.get_element())
# keep adding notes in the front in rev phonebook
rev.add_first(new)
# continue traversing through the list
curr = curr.get_next()
# return the reversed phonebook
return rev
tail_node.next = next_node
head = next_node
i = 0
node = next_node
i = i + 1
return dummy.next
def reverse(node, k):
tmp = node
previous = None
while tmp:
tmp.next, previous, tmp = previous, tmp, tmp.next
k = k - 1
if k == 0:
return previous, node
l = SingleLinkedList()
l.add_list_item(2)
l.add_list_item(1)
l.printall()
r = reverseKGroup(l.root, 2)
tmp = ""
while r is not None:
tmp = tmp + str(r.data) + '->'
r = r.next
print(tmp[:-2])
def printdata(head):
temp = head
while temp is not None:
print(temp.data)
temp = temp.next
chromedriver = "E:\Python36-32\chromedriver\chromedriver.exe"
driver = webdriver.Chrome(chromedriver)
driver.get("https://maps.google.com")
elem = driver.find_element_by_name("q")
time.sleep(.500)
elem.clear()
elem.send_keys("chennai to madurai")
elem.send_keys(Keys.RETURN)
assert "No results found." not in driver.page_source or "There is no Internet connection" not in driver.page_source
time.sleep(2)
link = driver.current_url
linkfile = requests.get(link)
content = linkfile.text
index = content.find(" km")
buscontent = content
SingleList = SingleLinkedList()
findbusroute(buscontent, SingleList)
printdata(SingleList)
driver.close()
driver.quit()
print("Finished")
# Series of steps involved to implement the requirement are -
# Build a single linked list by prompting user to enter values
# Traverse the list
# Convert the linked list to an array (this is to abide by the requirement which says linked list can be walked once,
# reverse, length or size cannot be used)
# class SearchFromEnd:
def kth_element_from_end(converted_list, k):
return converted_list[-k]
if __name__ == '__main__':
new_linked_list = SingleLinkedList()
nums = int(input("How many nodes do you want to create: "))
if nums <= 0:
raise ValueError("Invalid number of nodes..")
for i in range(nums):
value = int(input("Enter the value for the node:"))
new_linked_list.make_new_list(value)
# get list from linked list
converted_array = new_linked_list.traverse_and_convert()
kth_value = int(input("Enter the kth value to be returned from the end:"))
print(kth_element_from_end(converted_array, kth_value))