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70 lines
2.0 KiB
Python
70 lines
2.0 KiB
Python
from __future__ import print_function
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class Node: # create a Node
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def __init__(self, data):
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self.data = data # given data
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self.next = None # given next to None
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class Linked_List:
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def insert_tail(Head, data):
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if Head.next is None:
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Head.next = Node(data)
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else:
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Head.next.insert_tail(data)
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def insert_head(Head, data):
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tamp = Head
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if tamp is None:
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newNod = Node() # create a new Node
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newNod.data = data
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newNod.next = None
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Head = newNod # make new node to Head
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else:
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newNod = Node()
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newNod.data = data
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newNod.next = Head # put the Head at NewNode Next
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Head = newNod # make a NewNode to Head
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return Head
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def printList(Head): # print every node data
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tamp = Head
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while tamp is not None:
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print(tamp.data)
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tamp = tamp.next
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def delete_head(Head): # delete from head
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if Head is not None:
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Head = Head.next
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return Head # return new Head
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def delete_tail(Head): # delete from tail
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if Head is not None:
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tamp = Node()
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tamp = Head
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while tamp.next.next is not None: # find the 2nd last element
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tamp = tamp.next
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# delete the last element by give next None to 2nd last Element
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tamp.next = None
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return Head
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def isEmpty(Head):
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return Head is None # Return if Head is none
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def reverse(Head):
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prev = None
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current = Head
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while current:
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# Store the current node's next node.
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next_node = current.next
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# Make the current node's next point backwards
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current.next = prev
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# Make the previous node be the current node
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prev = current
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# Make the current node the next node (to progress iteration)
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current = next_node
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# Return prev in order to put the head at the end
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Head = prev
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