Exercise 06-19:
Change Program 6.22 to request the product and quantity sold from the user. Check if the product name entered exists in the dictionary and only then carry out the stock operation.
Answer:
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# Python From Scratch
# Author: Nilo Ney Coutinho Menezes
# Editora Novatec (c) 2010-2025 - LogiKraft 2025
# Site: https://pythonfromscratch.com
# ISBN: 978-85-7522-949-1 (Paperback), 978-85-7522-950-7 (hardcover), 978-85-7522-951-4 (ebook)
#
# File: chapter 06/exercise-06-19.py.py
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inventory = {
"tomato": [1000, 2.30],
"lettuce": [500, 0.45],
"potato": [2001, 1.20],
"beans": [100, 1.50],
}
total = 0
print("Sales:\n")
while True:
product = input("Product name (end to exit):")
if product == "end":
break
if product in inventory:
quantity = int(input("Quantity:"))
if quantity <= inventory[product][0]:
price = inventory[product][1]
cost = price * quantity
print(f"{product:12s}: {quantity:3d} x {price:6.2f} = {cost:6.2f}")
inventory[product][0] -= quantity
total += cost
else:
print("Requested quantity not available")
else:
print("Invalid product name")
print(f" Total cost: {total:21.2f}\n")
print("Inventory:\n")
for key, data in inventory.items():
print("Description: ", key)
print("Quantity: ", data[0])
print(f"Price: {data[1]:6.2f}\n")