Added Linked List files

new Circular LL, revised Doubly LL, revised LL

LinkedLists/CircularLinkedList.py

@@ -0,0 +1,116 @@
+class Node(object):
+
+	def __init__ (self, d, n = None):
+		self.data = d
+		self.next_node = n
+
+	def get_next (self):
+		return self.next_node
+
+	def set_next (self, n):
+		self.next_node = n
+		
+	def get_data (self):
+		return self.data
+
+	def set_data (self, d):
+		self.data = d
+		
+	def to_string (self):
+		return "Node value: " + str(self.data)
+
+class CircularLinkedList (object):
+
+	def __init__ (self, r = None):
+		self.root = r
+		self.size = 0
+
+	def get_size (self):
+		return self.size
+
+	def add (self, d):
+		if self.get_size() == 0:
+			self.root = Node(d)
+			self.root.set_next(self.root)
+		else:
+			new_node = Node (d, self.root.get_next())
+			self.root.set_next(new_node)
+		self.size += 1
+
+	def remove (self, d):
+		this_node = self.root
+		prev_node = None
+
+		while True:
+			if this_node.get_data() == d:	# found
+				if prev_node is not None:
+					prev_node.set_next(this_node.get_next())
+				else:
+					while this_node.get_next() != self.root:
+						this_node = this_node.get_next()
+					this_node.set_next(self.root.get_next())
+					self.root = self.root.get_next()
+				self.size -= 1
+				return True     # data removed
+			elif this_node.get_next() == self.root:
+				return False	# data not found
+			prev_node = this_node
+			this_node = this_node.get_next()
+
+	def find (self, d):
+		this_node = self.root
+		while True:
+			if this_node.get_data() == d:
+				return d
+			elif this_node.get_next() == self.root:
+				return False
+			this_node = this_node.get_next()
+		
+	def print_list (self):
+		print ("Print List..........")
+		if self.root is None:
+			return
+		this_node = self.root
+		print (this_node.to_string())
+		while this_node.get_next() != self.root:
+			this_node = this_node.get_next()
+			print (this_node.to_string())
+
+def main():
+	myList = CircularLinkedList()
+	myList.add(5)
+	myList.add(7)
+	myList.add(3)
+	myList.add(8)
+	myList.add(9)
+	print("Find 8", myList.find(8))
+	print("Find 12", myList.find(12))
+
+	cur = myList.root
+	print (cur.to_string())
+	for i in range(8):
+		cur = cur.get_next();
+		print (cur.to_string())
+
+	print("size="+str(myList.get_size()))
+	myList.print_list()
+	myList.remove(8)
+	print("size="+str(myList.get_size()))
+	print("Remove 15", myList.remove(15))
+	print("size="+str(myList.get_size()))
+	myList.remove(5)	# delete root node
+	myList.print_list()
+	
+main()
+
+
+
+
+
+
+
+
+
+
+
+

LinkedLists/DoublyLinkedList2.py

@@ -0,0 +1,113 @@
+class Node(object):
+
+	def __init__ (self, d, n = None, p = None):
+		self.data = d
+		self.next_node = n
+		self.prev_node = p
+
+	def get_next (self):
+		return self.next_node
+
+	def set_next (self, n):
+		self.next_node = n
+		
+	def get_prev (self):
+		return self.prev_node
+
+	def set_prev (self, p):
+		self.prev_node = p
+		
+	def get_data (self):
+		return self.data
+
+	def set_data (self, d):
+		self.data = d
+		
+	def to_string (self):
+		return "Node value: " + str(self.data)
+		
+	def has_next (self):
+		if self.get_next() is None:
+			return False
+		return True
+
+class DoublyLinkedList (object):
+
+	def __init__ (self, r = None):
+		self.root = r
+		self.last = r
+		self.size = 0
+
+	def get_size (self):
+		return self.size
+
+	def add (self, d):
+		if self.size == 0:
+			self.root = Node(d)
+			self.last = self.root
+		else:
+			new_node = Node(d, self.root)
+			self.root.set_prev(new_node)
+			self.root = new_node
+		self.size += 1
+
+	def remove (self, d):
+		this_node = self.root
+		while this_node is not None:
+			if this_node.get_data() == d:
+				if this_node.get_prev() is not None:
+					if this_node.has_next():	# delete a middle node
+						this_node.get_prev().set_next(this_node.get_next())
+						this_node.get_next().set_prev(this_node.get_prev())
+					else:	# delete last node
+						this_node.get_prev().set_next(None)
+						self.last = this_node.get_prev()
+				else: # delete root node
+					self.root = this_node.get_next()
+					this_node.get_next().set_prev(self.root)
+				self.size -= 1
+				return True     # data removed
+			else:
+				this_node = this_node.get_next()
+		return False  # data not found
+
+	def find (self, d):
+		this_node = self.root
+		while this_node is not None:
+			if this_node.get_data() == d:
+				return d
+			elif this_node.get_next() == self.root:
+				return False
+			else:
+				this_node = this_node.get_next()
+	
+	def print_list (self):
+		print ("Print List..........")
+		if self.root is None:
+			return
+		this_node = self.root
+		print (this_node.to_string())
+		while this_node.has_next():
+			this_node = this_node.get_next()
+			print (this_node.to_string())
+
+def main():
+	myList = DoublyLinkedList()
+	myList.add(5)
+	myList.add(9)
+	myList.add(3)
+	myList.add(8)
+	myList.add(9)
+	print("size="+str(myList.get_size()))
+	myList.print_list()
+	myList.remove(8)
+	print("size="+str(myList.get_size()))
+	print("Remove 15", myList.remove(15))
+	myList.add(21)
+	myList.add(22)
+	myList.remove(5)
+	myList.print_list()
+	print("size="+str(myList.get_size()))
+	print(myList.last.get_prev().to_string())
+
+main()

LinkedLists/LinkedList1.py

@@ -0,0 +1,118 @@
+class Node(object):
+
+	def __init__ (self, d, n = None):
+		self.data = d
+		self.next_node = n
+
+	def get_next (self):
+		return self.next_node
+
+	def set_next (self, n):
+		self.next_node = n
+		
+	def get_data (self):
+		return self.data
+
+	def set_data (self, d):
+		self.data = d
+		
+	def to_string (self):
+		return "Node value: " + str(self.data);
+		
+	def has_next (self):
+		if self.get_next() is None:
+			return False;
+		return True;
+
+	def compare_to (self, y):
+		if self.to_string() < y.to_string():
+			return -1;
+		elif self.to_string() > y.to_string():
+			return 1;
+		return 0;
+		
+
+class LinkedList (object):
+
+	def __init__ (self, r = None):
+		self.root = r
+		self.size = 0
+
+	def get_size (self):
+		return self.size
+
+	def add (self, d):
+		new_node = Node (d, self.root);
+		self.root = new_node;
+		self.size += 1;
+
+	def add_node (self, n):
+		n.set_next(self.root);
+		self.root = n;
+		self.size += 1;		
+		
+	def remove (self, d):
+		this_node = self.root
+		prev_node = None
+
+		while this_node:
+			if this_node.get_data() == d:
+				if prev_node:	# removing node that is not the root
+					prev_node.set_next(this_node.get_next())
+				else:	# removing root node
+					self.root = this_node.get_next()
+				self.size -= 1
+				return True     # data removed
+			else:
+				prev_node = this_node
+				this_node = this_node.get_next()
+		return False  # data not found
+
+	def find (self, d):
+		this_node = self.root
+		while this_node:
+			if this_node.get_data() == d:
+				return d
+			else:
+				this_node = this_node.get_next()
+		return None
+		
+	def print_list (self):
+		print ("Print List..........");
+		if self.root is None:
+			return;
+		current = self.root;
+		print (current.to_string());
+		while current.has_next():
+			current = current.get_next();
+			print (current.to_string());
+			
+	def sort (self):
+		if self.size > 1:
+			newlist = [];
+			current = self.root;
+			newlist.append(self.root);
+			while current.has_next():
+				current = current.get_next();
+				newlist.append(current);
+			newlist = sorted(newlist, key = lambda node: node.get_data(), reverse = True);
+			newll = LinkedList();
+			for node in newlist:
+				newll.add_node(node);
+			return newll;
+		return self;
+
+myList = LinkedList()
+myList.add(5)
+myList.add(9)
+myList.add(3)
+myList.add(8)
+myList.add(9)
+print("size="+str(myList.get_size()))
+myList.print_list();
+myList = myList.sort();
+myList.print_list();
+myList.remove(8)
+print("size="+str(myList.get_size()))
+print(myList.remove(12))
+print("size="+str(myList.get_size()))

LinkedLists/LinkedList2.py

@@ -0,0 +1,126 @@
+class Node(object):
+
+	def __init__ (self, d, n = None):
+		self.data = d
+		self.next_node = n
+
+	def get_next (self):
+		return self.next_node
+
+	def set_next (self, n):
+		self.next_node = n
+		
+	def get_data (self):
+		return self.data
+
+	def set_data (self, d):
+		self.data = d
+		
+	def has_next (self):
+		if self.get_next() is None:
+			return False
+		return True
+		
+	def to_string (self):
+		return "Node value: " + str(self.data)
+		
+class LinkedList (object):
+
+	def __init__ (self, r = None):
+		self.root = r
+		self.size = 0
+
+	def get_size (self):
+		return self.size
+
+	def add (self, d):
+		new_node = Node (d, self.root)
+		self.root = new_node
+		self.size += 1
+
+	def add_node (self, n):
+		n.set_next(self.root)
+		self.root = n
+		self.size += 1
+		
+	def remove (self, d):
+		this_node = self.root
+		prev_node = None
+
+		while this_node is not None:
+			if this_node.get_data() == d:
+				if prev_node is not None:
+					prev_node.set_next(this_node.get_next())
+				else:
+					self.root = this_node.get_next()
+				self.size -= 1
+				return True     # data removed
+			else:
+				prev_node = this_node
+				this_node = this_node.get_next()
+		return False  # data not found
+
+	def find (self, d):
+		this_node = self.root
+		while this_node is not None:
+			if this_node.get_data() == d:
+				return d
+			elif this_node.get_next() == None:
+				return False
+			else:
+				this_node = this_node.get_next()
+				
+	def print_list (self):
+		print ("Print List..........")
+		if self.root is None:
+			return
+		this_node = self.root
+		print (this_node.to_string())
+		while this_node.has_next():
+			this_node = this_node.get_next()
+			print (this_node.to_string())
+			
+	def sort (self):
+		if self.size > 1:
+			newlist = [];
+			current = self.root;
+			newlist.append(self.root);
+			while current.has_next():
+				current = current.get_next();
+				newlist.append(current);
+			newlist = sorted(newlist, key = lambda node: node.get_data(), reverse = True);
+			newll = LinkedList();
+			for node in newlist:
+				newll.add_node(node);
+			return newll;
+		return self;
+		
+def main():
+	myList = LinkedList()
+	myList.add(5)
+	myList.add(9)
+	myList.add(3)
+	myList.add(8)
+	myList.add(9)
+	print("size="+str(myList.get_size()))
+	myList.print_list()
+	myList = myList.sort()
+	myList.print_list()
+	myList.remove(8)
+	print("size="+str(myList.get_size()))
+	print("Remove 15", myList.remove(15))
+	print("size="+str(myList.get_size()))
+	print("Find 25", myList.find(25))
+	myList.print_list()
+	
+main()
+
+
+
+
+
+
+
+
+
+