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 __str__(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) while this_node.get_next() != self.root: this_node = this_node.get_next() print (this_node) 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) for i in range(8): cur = cur.get_next(); print (cur) 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()