def test_size(self):
node = BSTNode("e")
assert node.size() == 1
node.add("g")
node.add("o")
node.add("h")
node.add("k")
node.add("m")
node.add("l")
assert node.size() == 7
class MovieLib:
"""A movie library.
Implemented using a BST.
"""
def __init__(self):
"""Initialise a movie library."""
self.bst = None
def __str__(self):
"""Return a string representation of the library.
The string will be created by an in-order traversal.
"""
if self.bst is not None:
return str(self.bst)
def size(self):
"""Return the number of movies in the library."""
if self.bst is None:
return 0
return self.bst.size()
def search(self, title):
"""Return Movie with matching title if there, or None.
Args:
title: a string representing a movie title.
"""
if self.bst is not None:
return self.bst.search(Movie(title))
def add(self, title, date, runtime):
"""Add a new movie to the library.
Args:
title - the title of the movie
date - the date the movie was released
runtime - the running time of the movie
Returns:
the movie file that was added, or None
"""
add_movie = Movie(title, date, runtime)
if self.bst is None:
self.bst = BSTNode(add_movie)
return add_movie
return self.bst.add(add_movie)
def remove(self, title):
"""Remove and return the a movie object with the given title, if there.
Args:
title - the title of the movie to be removed
"""
if self.bst is not None:
removed = self.bst.remove(Movie(title))
if self.bst.size() == 0: # If tree is now empty
self.bst = None # Set reference to None
return removed
def _testadd():
library = MovieLib()
library.add("Memento", "11/10/2000", 113)
print(str(library))
print("> adding Melvin and Howard")
library.add("Melvin and Howard", "19/09/1980", 95)
print(str(library))
print("> adding a second version of Melvin and Howard")
library.add("Melvin and Howard", "21/03/2007", 112)
print(str(library))
print("> adding Mellow Mud")
library.add("Mellow Mud", "21/09/2016", 92)
print(str(library))
print("> adding Melody")
library.add("Melody", "21/03/2007", 113)
print(str(library))
return library
def _test():
library = MovieLib()
library.add("B", "b", 1)
print("Library:", library)
print("adding", "A")
library.add("A", "a", 1)
print("Library:", library)
print("removing", "A")
library.remove("A")
print("Library:", library)
print("adding", "C")
library.add("C", "c", 1)
print("Library:", library)
print("removing", "C")
library.remove("C")
print("Library:", library)
print("adding", "F")
library.add("F", "f", 1)
print("Library:", library)
print("removing", "B")
library.remove("B")
print("Library:", library)
print("adding", "C")
library.add("C", "c", 1)
print("Library:", library)
print("adding", "D")
library.add("D", "d", 1)
print("Library:", library)
print("adding", "C")
library.add("C", "c", 1)
print("Library:", library)
print("adding", "E")
library.add("E", "e", 1)
print("Library:", library)
print("removing", "B")
library.remove("B")
print("Library:", library)
print("removing", "D")
library.remove("D")
print("Library:", library)
print("removing", "C")
library.remove("C")
print("Library:", library)
print("removing", "E")
library.remove("E")
print("Library:", library)
print("adding", "L")
library.add("L", "l", 1)
print("Library:", library)
print("adding", "H")
library.add("H", "h", 1)
print("Library:", library)
print("adding", "I")
library.add("I", "i", 1)
print("Library:", library)
print("adding", "G")
library.add("G", "g", 1)
print("Library:", library)
print("removing", "L")
library.remove("L")
print("Library:", library)
print("removing", "H")
library.remove("H")
print("Library:", library)
print("removing", "I")
library.remove("I")
print("Library:", library)
print("removing", "G")
library.remove("G")
print("Library:", library)
