File Size Calculation

import os
def calculate_directory_size(directory_path):
    total_size = 0
    dir_stack = [directory_path]
    while dir_stack:
        current_path = dir_stack.pop()
        for item in os.listdir(current_path):
            full_path = os.path.join(current_path, item)
            if os.path.isfile(full_path):
                total_size += os.path.getsize(full_path)
            else:
                dir_stack.append(full_path)
    return total_size

print(calculate_directory_size('/path/to/directory'))

Multi-level Menu Navigation

menu = {
    'main': {'sub1': {}, 'sub2': {}},
    'sub1': {'option1': {}, 'option2': {}}
}

current_menu = ['main']
while current_menu:
    for option in current_menu[-1]:
        print(option)
    selection = input('>>> ').upper()
    if selection == 'B':
        current_menu.pop()
    elif selection == 'Q':
        current_menu.clear()
    elif selection in current_menu[-1]:
        current_menu.append(current_menu[-1][selection])

File Monitoring

def monitor_file_changes(file_path):
    with open(file_path, 'r', encoding='utf-8') as f:
        while True:
            line = f.readline()
            if line:
                yield line

for change in monitor_file_changes('log.txt'):
    print(change)

Red Packet Distribution

import random

def distribute_money(total_amount, recipients):
    divisions = random.sample(range(1, total_amount*100), recipients-1)
    divisions.sort()
    divisions = [0] + divisions + [total_amount*100]
    for i in range(len(divisions)-1):
        yield (divisions[i+1] - divisions[i]) / 100

for amount in distribute_money(200, 5):
    print(f"Received: {amount}")

Recursvie Path Finding

people = ['Alice', 'Bob', 'Charlie', 'David', 'Eve']

def ask_for_directions(contacts):
    if not contacts:
        return "No directions found"
    person = contacts[0]
    if person == 'Eve':
        return f"{person} says: The destination is near the central park"
    print(f"Asking {person} for directions")
    return ask_for_directions(contacts[1:])

print(ask_for_directions(people))

Shopipng Cart Implementation

products = [
    {'name': 'Laptop', 'price': 999},
    {'name': 'Phone', 'price': 699},
    {'name': 'Tablet', 'price': 399}
]

cart = {}
budget = float(input("Enter your budget: "))

while True:
    for idx, product in enumerate(products, 1):
        print(f"{idx}. {product['name']} - ${product['price']}")
    
    choice = input("Select product (Q to quit): ")
    if choice.upper() == 'Q':
        break
    elif choice.isdigit() and 0 < int(choice) <= len(products):
        selected = products[int(choice)-1]
        cart[selected['name']] = cart.get(selected['name'], 0) + 1

print("Your cart:")
for item, quantity in cart.items():
    print(f"{item}: {quantity}")