78 lines
1.8 KiB
Python
78 lines
1.8 KiB
Python
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class Node(object):
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def __init__ (self, d, n = None, p = None):
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self.data = d
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self.next_node = n
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self.prev_node = p
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def get_next (self):
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return self.next_node
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def set_next (self, n):
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self.next_node = n
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def get_prev (self):
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return self.prev_node
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def set_prev (self, p):
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self.prev_node = p
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def get_data (self):
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return self.data
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def set_data (self, d):
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self.data = d
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class LinkedList (object):
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def __init__(self, r = None):
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self.root = r
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self.size = 0
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def get_size (self):
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return self.size
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def add (self, d):
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new_node = Node (d, self.root)
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if self.root:
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self.root.set_prev(new_node)
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self.root = new_node
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self.size += 1
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def remove (self, d):
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this_node = self.root
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while this_node:
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if this_node.get_data() == d:
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next = this_node.get_next()
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prev = this_node.get_prev()
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if next:
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next.set_prev(prev)
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if prev:
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prev.set_next(next)
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else:
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self.root = this_node
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self.size -= 1
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return True # data removed
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else:
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this_node = this_node.get_next()
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return False # data not found
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def find (self, d):
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this_node = self.root
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while this_node:
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if this_node.get_data() == d:
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return d
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else:
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this_node = this_node.get_next()
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return None
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myList = LinkedList()
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myList.add(5)
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myList.add(8)
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myList.add(12)
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myList.remove(8)
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print(myList.remove(12))
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print(myList.find(5))
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