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Tutorial 3

This commit is contained in:
Marcus Vinicius de Carvalho 2025-02-27 19:31:48 +08:00
parent bc6f105faa
commit add0b19505
6 changed files with 661 additions and 0 deletions
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99
T3/Answer/Q2 - level_order_traversal.py Normal file
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class Bst_node:
def __init__(self, item):
self.item = item
self.left = None
self.right = None
class Queue_node:
def __init__(self, data):
self.data = data
self.next_ptr = None
class Queue:
def __init__(self):
self.head = None
self.tail = None
def insert_bst_node(node_ref, value):
if node_ref[0] is None:
node_ref[0] = Bst_node(value)
else:
if value < node_ref[0].item:
if node_ref[0].left is None:
node_ref[0].left = Bst_node(value)
else:
insert_bst_node([node_ref[0].left], value)
elif value > node_ref[0].item:
if node_ref[0].right is None:
node_ref[0].right = Bst_node(value)
else:
insert_bst_node([node_ref[0].right], value)
def enqueue(queue, node):
new_node = Queue_node(node)
if is_empty(queue.head):
queue.head = new_node
else:
queue.tail.next_ptr = new_node
queue.tail = new_node
def dequeue(queue):
if queue.head is not None:
node = queue.head.data
queue.head = queue.head.next_ptr
if queue.head is None: # If the queue becomes empty
queue.tail = None
return node
return None
def is_empty(head):
return head is None
def remove_all(node_ref):
if node_ref[0] is not None:
remove_all([node_ref[0].left])
remove_all([node_ref[0].right])
del node_ref[0]
def level_order_traversal(root):
queue = Queue()
temp = root
if temp is not None:
enqueue(queue, temp)
while not is_empty(queue.head):
temp = dequeue(queue)
print(temp.item, end=' ')
if temp.left is not None:
enqueue(queue, temp.left)
if temp.right is not None:
enqueue(queue, temp.right)
# Main function to run the program.
if __name__ == "__main__":
c = 1
root = [None] # Use a list to allow modification of the root reference
print("1: Insert an integer into the binary search tree;")
print("2: Print the level-order traversal of the binary search tree;")
print("0: Quit;")
while c != 0:
c = int(input("Please input your choice(1/2/0): "))
if c == 1:
i = int(input("Input an integer that you want to insert into the Binary Search Tree: "))
insert_bst_node(root, i)
elif c == 2:
print("The resulting level-order traversal of the binary search tree is: ", end="")
level_order_traversal(root[0]) # Pass the actual root node
print()
elif c == 0:
remove_all(root)
else:
print("Choice unknown;")

115
T3/Answer/Q3 - pre_order_iterative.py Normal file
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class Bst_node:
def __init__(self, item):
self.item = item
self.left = None
self.right = None
class Stack_node:
def __init__(self, data):
self.data = data
self.next = None
class Stack:
def __init__(self):
self.top = None
def insert_bst_node(node_ref, value):
if node_ref[0] is None:
node_ref[0] = Bst_node(value)
else:
if value < node_ref[0].item:
if node_ref[0].left is None:
node_ref[0].left = Bst_node(value)
else:
insert_bst_node([node_ref[0].left], value)
elif value > node_ref[0].item:
if node_ref[0].right is None:
node_ref[0].right = Bst_node(value)
else:
insert_bst_node([node_ref[0].right], value)
def push(stack, node):
temp = Stack_node(node)
if stack.top is None:
stack.top = temp
temp.next = None
else:
temp.next = stack.top
stack.top = temp
def pop(s):
if s.top is None:
return None
temp = s.top.next
ptr = s.top.data
s.top = temp
return ptr
def peek(s):
if s.top is None:
return None
return s.top.data
def isEmpty(s):
return s.top is None
def removeAll(node_ref):
if node_ref[0] is not None:
removeAll([node_ref[0].left])
removeAll([node_ref[0].right])
node_ref[0] = None
def pre_order_iterative(root):
stack = Stack()
temp = root
if temp is None:
return
push(stack, temp)
while not isEmpty(stack):
temp = pop(stack)
print(temp.item, end=" ")
if temp.right is not None:
push(stack, temp.right)
if temp.left is not None:
push(stack, temp.left)
def main():
root = [None] # Using list to simulate pointer reference
print("1: Insert an integer into the binary search tree;")
print("2: Print the pre-order traversal of the binary search tree;")
print("0: Quit;")
while True:
try:
c = int(input("Please input your choice(1/2/0): "))
if c == 1:
i = int(input("Input an integer that you want to insert into the Binary Search Tree: "))
insert_bst_node(root, i)
elif c == 2:
print("The resulting pre-order traversal of the binary search tree is: ", end="")
pre_order_iterative(root[0])
print()
elif c == 0:
removeAll(root)
break
else:
print("Choice unknown;")
except ValueError:
print("Invalid input")
continue
if __name__ == "__main__":
main()

134
T3/Answer/Q4 - max_depth.py Normal file
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class Bt_node:
def __init__(self, item):
self.item = item
self.left = None
self.right = None
class Stack_node:
def __init__(self, btnode):
self.btnode = btnode
self.next = None
class Stack:
def __init__(self):
self.top = None
def create_bt_node(item):
return Bt_node(item)
def push(stack, node):
temp = Stack_node(node)
if stack.top is None:
stack.top = temp
temp.next = None
else:
temp.next = stack.top
stack.top = temp
def pop(stack):
if stack.top is None:
return None
temp = stack.top.next
ptr = stack.top.btnode
stack.top = temp
return ptr
def print_tree(node):
if node is None:
return
print_tree(node.left)
print(node.item, end=" ")
print_tree(node.right)
def create_tree():
stack = Stack()
root = None
print("Input an integer that you want to add to the binary tree. Any Alpha value will be treated as NULL.")
try:
item = input("Enter an integer value for the root: ")
root = create_bt_node(int(item))
push(stack, root)
except ValueError:
return None
while True:
temp = pop(stack)
if temp is None:
break
try:
item = input(f"Enter an integer value for the Left child of {temp.item}: ")
temp.left = create_bt_node(int(item))
except ValueError:
temp.left = None
try:
item = input(f"Enter an integer value for the Right child of {temp.item}: ")
temp.right = create_bt_node(int(item))
except ValueError:
temp.right = None
if temp.right is not None:
push(stack, temp.right)
if temp.left is not None:
push(stack, temp.left)
return root
def remove_all(node):
if node is not None:
remove_all(node.left)
remove_all(node.right)
node.left = None
node.right = None
def max_depth(node):
if node is None:
return -1
else:
left_depth = max_depth(node.left)
right_depth = max_depth(node.right)
if left_depth > right_depth:
return left_depth + 1
else:
return right_depth + 1
def main():
root = None
print("1: Create a binary tree.")
print("2: Find the maximum depth of the binary tree.")
print("0: Quit;")
while True:
try:
c = int(input("\nPlease input your choice(1/2/0): "))
if c == 1:
root = None # Clear existing tree
root = create_tree()
print("The resulting binary tree is: ", end="")
print_tree(root)
print()
elif c == 2:
depth = max_depth(root)
print(f"The maximum depth of the binary tree is: {depth}")
root = None
elif c == 0:
if root:
remove_all(root)
break
else:
print("Choice unknown;")
except ValueError:
continue
if __name__ == "__main__":
main()

88
T3/Base/Q2 - level_order_traversal.py Normal file
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class Bst_node:
def __init__(self, item):
self.item = item
self.left = None
self.right = None
class Queue_node:
def __init__(self, data):
self.data = data
self.next_ptr = None
class Queue:
def __init__(self):
self.head = None
self.tail = None
def insert_bst_node(node_ref, value):
if node_ref[0] is None:
node_ref[0] = Bst_node(value)
else:
if value < node_ref[0].item:
if node_ref[0].left is None:
node_ref[0].left = Bst_node(value)
else:
insert_bst_node([node_ref[0].left], value)
elif value > node_ref[0].item:
if node_ref[0].right is None:
node_ref[0].right = Bst_node(value)
else:
insert_bst_node([node_ref[0].right], value)
def enqueue(queue, node):
new_node = Queue_node(node)
if is_empty(queue.head):
queue.head = new_node
else:
queue.tail.next_ptr = new_node
queue.tail = new_node
def dequeue(queue):
if queue.head is not None:
node = queue.head.data
queue.head = queue.head.next_ptr
if queue.head is None: # If the queue becomes empty
queue.tail = None
return node
return None
def is_empty(head):
return head is None
def remove_all(node_ref):
if node_ref[0] is not None:
remove_all([node_ref[0].left])
remove_all([node_ref[0].right])
del node_ref[0]
def level_order_traversal(root):
raise NotImplementedError
# Main function to run the program.
if __name__ == "__main__":
c = 1
root = [None] # Use a list to allow modification of the root reference
print("1: Insert an integer into the binary search tree;")
print("2: Print the level-order traversal of the binary search tree;")
print("0: Quit;")
while c != 0:
c = int(input("Please input your choice(1/2/0): "))
if c == 1:
i = int(input("Input an integer that you want to insert into the Binary Search Tree: "))
insert_bst_node(root, i)
elif c == 2:
print("The resulting level-order traversal of the binary search tree is: ", end="")
level_order_traversal(root[0]) # Pass the actual root node
print()
elif c == 0:
remove_all(root)
else:
print("Choice unknown;")

100
T3/Base/Q3 - pre_order_iterative.py Normal file
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class Bst_node:
def __init__(self, item):
self.item = item
self.left = None
self.right = None
class Stack_node:
def __init__(self, data):
self.data = data
self.next = None
class Stack:
def __init__(self):
self.top = None
def insert_bst_node(node_ref, value):
if node_ref[0] is None:
node_ref[0] = Bst_node(value)
else:
if value < node_ref[0].item:
if node_ref[0].left is None:
node_ref[0].left = Bst_node(value)
else:
insert_bst_node([node_ref[0].left], value)
elif value > node_ref[0].item:
if node_ref[0].right is None:
node_ref[0].right = Bst_node(value)
else:
insert_bst_node([node_ref[0].right], value)
def push(stack, node):
temp = Stack_node(node)
if stack.top is None:
stack.top = temp
temp.next = None
else:
temp.next = stack.top
stack.top = temp
def pop(s):
if s.top is None:
return None
temp = s.top.next
ptr = s.top.data
s.top = temp
return ptr
def peek(s):
if s.top is None:
return None
return s.top.data
def isEmpty(s):
return s.top is None
def removeAll(node_ref):
if node_ref[0] is not None:
removeAll([node_ref[0].left])
removeAll([node_ref[0].right])
node_ref[0] = None
def pre_order_iterative(root):
raise NotImplementedError
def main():
root = [None] # Using list to simulate pointer reference
print("1: Insert an integer into the binary search tree;")
print("2: Print the pre-order traversal of the binary search tree;")
print("0: Quit;")
while True:
try:
c = int(input("Please input your choice(1/2/0): "))
if c == 1:
i = int(input("Input an integer that you want to insert into the Binary Search Tree: "))
insert_bst_node(root, i)
elif c == 2:
print("The resulting pre-order traversal of the binary search tree is: ", end="")
pre_order_iterative(root[0])
print()
elif c == 0:
removeAll(root)
break
else:
print("Choice unknown;")
except ValueError:
print("Invalid input")
continue
if __name__ == "__main__":
main()

125
T3/Base/Q4 - max_depth.py Normal file
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class Bt_node:
def __init__(self, item):
self.item = item
self.left = None
self.right = None
class Stack_node:
def __init__(self, btnode):
self.btnode = btnode
self.next = None
class Stack:
def __init__(self):
self.top = None
def create_bt_node(item):
return Bt_node(item)
def push(stack, node):
temp = Stack_node(node)
if stack.top is None:
stack.top = temp
temp.next = None
else:
temp.next = stack.top
stack.top = temp
def pop(stack):
if stack.top is None:
return None
temp = stack.top.next
ptr = stack.top.btnode
stack.top = temp
return ptr
def print_tree(node):
if node is None:
return
print_tree(node.left)
print(node.item, end=" ")
print_tree(node.right)
def create_tree():
stack = Stack()
root = None
print("Input an integer that you want to add to the binary tree. Any Alpha value will be treated as NULL.")
try:
item = input("Enter an integer value for the root: ")
root = create_bt_node(int(item))
push(stack, root)
except ValueError:
return None
while True:
temp = pop(stack)
if temp is None:
break
try:
item = input(f"Enter an integer value for the Left child of {temp.item}: ")
temp.left = create_bt_node(int(item))
except ValueError:
temp.left = None
try:
item = input(f"Enter an integer value for the Right child of {temp.item}: ")
temp.right = create_bt_node(int(item))
except ValueError:
temp.right = None
if temp.right is not None:
push(stack, temp.right)
if temp.left is not None:
push(stack, temp.left)
return root
def remove_all(node):
if node is not None:
remove_all(node.left)
remove_all(node.right)
node.left = None
node.right = None
def max_depth(node):
raise NotImplementedError
def main():
root = None
print("1: Create a binary tree.")
print("2: Find the maximum depth of the binary tree.")
print("0: Quit;")
while True:
try:
c = int(input("\nPlease input your choice(1/2/0): "))
if c == 1:
root = None # Clear existing tree
root = create_tree()
print("The resulting binary tree is: ", end="")
print_tree(root)
print()
elif c == 2:
depth = max_depth(root)
print(f"The maximum depth of the binary tree is: {depth}")
root = None
elif c == 0:
if root:
remove_all(root)
break
else:
print("Choice unknown;")
except ValueError:
continue
if __name__ == "__main__":
main()