singly linked list in python
class Node:
def __init__(self, data, next1):
self.data = data
self.next = next1
class Linkedlist:
def __init__(self):
self.head = None
self.size = 0
def length(self):
return self.size
def is_empty(self):
return self.size == 0
def insert_at_the_beginning(self, data):
self.insert_with_index(0, data)
def insert_at_the_ending(self, data):
self.insert_with_index(self.size, data)
def insert_with_index(self, index, data):
if index > self.size or index < 0:
print("check given", index, "index value and enter again")
return False
if index == 0:
self.head = Node(data, self.head)
else:
current = self.head
for i in range(index - 1):
current = current.next
current.next = Node(data, current.next)
self.size += 1
def peek_top(self):
return self.peek_index(0)
def peek_bottom(self):
return self.peek_index(self.size - 1)
def peek_index(self, index):
if index >= self.size or index < 0:
print("check given", index, "index value and enter again")
return False
current = self.head
for i in range(index):
current = current.next
return current.data
def peek_element(self, data):
current = self.head
while current.data != data:
if current.next is None:
print("element", data, "not found")
return False
current = current.next
print("element", data, "is found")
return True
def delete_top_element(self):
return self.delete_with_index(0)
def delete_bottom_element(self):
return self.delete_with_index(self.size - 1)
def delete_with_index(self, index):
if index >= self.size or index < 0:
print("check given", index, "index value and enter again")
return False
self.size -= 1
if index == 0:
temp = self.head
self.head = self.head.next
return temp.data
current = self.head
for i in range(index - 1):
current = current.next
temp = current.next
current.next = current.next.next
return temp.data
def delete_with_value(self, data):
current = self.head
previous = current
while current.data != data:
if current.next is None:
print("element", data, "not found")
return False
previous = current
current = current.next
temp = previous.next
previous.next = current.next
print("element", data, "is found and deleted")
self.size -= 1
return temp.data
def print_val(self):
current = self.head
while current:
print(current.data, "\b--->", end="")
current = current.next
print()
linked_list = Linkedlist()
def trail1():
linked_list.insert_at_the_beginning(45)
linked_list.insert_at_the_beginning(65)
linked_list.insert_at_the_beginning(34)
linked_list.insert_at_the_beginning(56)
linked_list.insert_at_the_beginning(78)
linked_list.insert_at_the_beginning(98)
linked_list.insert_at_the_beginning(63)
linked_list.insert_at_the_beginning(31)
linked_list.print_val()
def trail2():
linked_list.insert_at_the_beginning(78)
linked_list.insert_at_the_ending(67778)
linked_list.insert_at_the_ending(899)
linked_list.insert_at_the_ending(99)
linked_list.print_val()
trail1()
def trail3():
linked_list.insert_at_the_beginning(34)
linked_list.insert_at_the_beginning(56)
linked_list.insert_at_the_beginning(78)
linked_list.insert_at_the_beginning(31)
linked_list.insert_at_the_ending(12)
linked_list.insert_at_the_ending(14)
linked_list.insert_at_the_ending(56)
linked_list.insert_with_index(90, 345)
linked_list.insert_with_index(5, 23)
print(linked_list.peek_index(2))
print(linked_list.peek_bottom())
print(linked_list.peek_top())
linked_list.peek_element(16)
linked_list.peek_element(33)
linked_list.insert_at_the_beginning(128)
linked_list.insert_at_the_beginning(784)
linked_list.insert_at_the_beginning(314)
linked_list.print_val()
print(linked_list.delete_with_index(5))
linked_list.print_val()
print(linked_list.delete_top_element())
linked_list.print_val()
print(linked_list.delete_bottom_element())
linked_list.print_val()
linked_list.delete_with_value(12)
linked_list.print_val()
# trail2()
# this is siva
# signing off
if __name__ == "__main__":
trail3()