6f4622e530
Overwriting the inbuilt '__str__' method to print the Node, rather than creating a new method and calling it.
117 lines
2.3 KiB
Python
117 lines
2.3 KiB
Python
class Node(object):
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def __init__ (self, d, n = None):
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self.data = d
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self.next_node = n
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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_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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def __str__(self):
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return "Node value: " + str(self.data)
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class CircularLinkedList (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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if self.get_size() == 0:
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self.root = Node(d)
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self.root.set_next(self.root)
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else:
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new_node = Node (d, self.root.get_next())
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self.root.set_next(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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prev_node = None
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while True:
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if this_node.get_data() == d: # found
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if prev_node is not None:
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prev_node.set_next(this_node.get_next())
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else:
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while this_node.get_next() != self.root:
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this_node = this_node.get_next()
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this_node.set_next(self.root.get_next())
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self.root = self.root.get_next()
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self.size -= 1
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return True # data removed
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elif this_node.get_next() == self.root:
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return False # data not found
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prev_node = this_node
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this_node = this_node.get_next()
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def find (self, d):
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this_node = self.root
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while True:
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if this_node.get_data() == d:
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return d
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elif this_node.get_next() == self.root:
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return False
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this_node = this_node.get_next()
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def print_list (self):
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print ("Print List..........")
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if self.root is None:
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return
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this_node = self.root
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print (this_node)
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while this_node.get_next() != self.root:
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this_node = this_node.get_next()
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print (this_node)
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def main():
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myList = CircularLinkedList()
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myList.add(5)
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myList.add(7)
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myList.add(3)
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myList.add(8)
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myList.add(9)
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print("Find 8", myList.find(8))
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print("Find 12", myList.find(12))
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cur = myList.root
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print (cur)
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for i in range(8):
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cur = cur.get_next();
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print (cur)
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print("size="+str(myList.get_size()))
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myList.print_list()
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myList.remove(8)
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print("size="+str(myList.get_size()))
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print("Remove 15", myList.remove(15))
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print("size="+str(myList.get_size()))
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myList.remove(5) # delete root node
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myList.print_list()
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main()
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