Python Object-Oriented Programming: Shopping cart class with item management and total calculation

Last update on December 21 2024 07:40:34 (UTC/GMT +8 hours)

Write a Python program to create a class representing a shopping cart. Include methods for adding and removing items, and calculating the total price.

Sample Solution:

Python Code:

# Define a class called ShoppingCart to represent a shopping cart
class ShoppingCart:
    # Initialize the shopping cart with an empty list of items
    def __init__(self):
        self.items = []

    # Add an item with a name and quantity to the shopping cart
    def add_item(self, item_name, qty):
        item = (item_name, qty)
        self.items.append(item)

    # Remove an item with a specific name from the shopping cart
    def remove_item(self, item_name):
        for item in self.items:
            if item[0] == item_name:
                self.items.remove(item)
                break

    # Calculate and return the total quantity of items in the shopping cart
    def calculate_total(self):
        total = 0
        for item in self.items:
            total += item[1]
        return total

# Example usage
# Create an instance of the ShoppingCart class
cart = ShoppingCart()

# Add items to the shopping cart
cart.add_item("Papaya", 100)
cart.add_item("Guava", 200)
cart.add_item("Orange", 150)

# Display the current items in the cart and calculate the total quantity
print("Current Items in Cart:")
for item in cart.items:
    print(item[0], "-", item[1])

total_qty = cart.calculate_total()
print("Total Quantity:", total_qty)

# Remove an item from the cart, display the updated items, and recalculate the total quantity
cart.remove_item("Orange")
print("\nUpdated Items in Cart after removing Orange:")
for item in cart.items:
    print(item[0], "-", item[1])

total_qty = cart.calculate_total()
print("Total Quantity:", total_qty) 

Sample Output:

Current Items in Cart:
Papaya - 100
Guava - 200
Orange - 150
Total Quantity: 450

Updated Items in Cart after removing Orange:
Papaya - 100
Guava - 200
Total Quantity: 300

Explanation:

In this above exercise -

• We define a ShoppingCart class representing a shopping cart. It has an attribute called items, which is initially an empty list.
• The "add_item()" method takes an item name and quantity as arguments and adds them as a tuple to the items list. This adds the item to the cart.
• The "remove_item()" method removes the first occurrence of an item with the specified name from the items list. It iterates over the list and checks if the current item's name matches the specified name. If a match is found, it removes the item from the list and breaks out of the loop.
• The "calculate_total()" method calculates and returns the total quantity of all items in the cart. It iterates over the items list and accumulates the quantity of each item.
• In the example usage section, we create an instance of the ShoppingCart class called cart. We add several items to the cart using the "add_item()" method and display the current items in the cart.
• We calculate and display the total quantity of items using the "calculate_total()" method.
• The "remove_item()" method is used to remove an item from the cart and then display the updated items.

Flowchart:

Python Code Editor:

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