Question

Problem Definition:
a.Create and design a program that will determine a product, price, quantity, total amount etc.
b.Demonstrate the concept of Python Program using Selection and Loop Control Statement.
c.Construct the Flowchart to show the program logic sequence.
d.Herewith are the requirements:

i.Store Name
ii.Name of Customer
iii.Address
iv.Contact Number
v.List of Product to offer
vi.Price List
vii.Cash Amount
viii.Total Quantity of Product
ix.Total Amount to be paid.
x.Changed
xi.ASCII ART for your Product
xii.Sample Output

Answer 1

#This part greets the user, and lets the user know that the application has started
print("Hello there!")
#This starts off the loop, but this variable may be changed later on
cont = "yes"
#This is the actual loop
while cont == "yes" or cont == "Yes" or cont == "YES":
  print("Choose an option below:")
#This shows the options
  print("1) Calculate the value of different product sizes")
  print("2) Calculate the sale price")
  print("3) Calculate the discount")
  print("4) Create a shopping list")
  print("5) Exit")
#This part lets the user choose what they would like to do
  option = float(input("Choose an option (1/2/3/4/5): "))  
#This is what happens if the user chooses Option 4
  if option == 4:
#This is the "Shopping list" part of the application below
    import os,sys,time
    sl = []
    try:
      f = open("Your_shopping_list.txt","r")
      for line in f:
        sl.append(line.strip())
      f.close()
    except:
        pass
    def mainScreen():
      print("Your list contains",len(sl),"items.")
      print("Please choose from the following options:")
      print("1) Add to the list")
      print("2) Delete from the list")
      print("3) View the list")
      print("4) Quit the program")
      choice = input("Enter your choice here (1/2/3/4): ")
      if len(choice) > 0:
        if choice == "1":
          addScreen()
        elif choice == "2":
          deleteScreen()
        elif choice == "3":
          viewScreen()
        elif choice == "4":
          sys.exit()
        else:
          mainScreen()
      else:
        mainScreen()
    def addScreen():
      print("Please enter the name of the item that you want to add.")
      print("Press ENTER to return to the main menu.")
      item = input("Item: ")
      if len(item) > 0:
        sl.append(item)
        print("Item added.")
        saveList()
        time.sleep(1)
        addScreen()
      else:
        mainScreen()
    def viewScreen():
      for item in sl:
        print(item)
      print("Press ENTER to return to the main menu")
      input()
      mainScreen()
    def deleteScreen():
      global sl
      count = 0
      for item in sl:
        print(count, " - ", item)
        count = count + 1
      print("Press ENTER to return to the main menu.")
      print("Which item do you want to remove?")
      choice = input("Enter your choice here: ")
      if len(choice) > 0:
        try:
          del sl[int(choice)]
          print("Item deleted...")
          saveList()
          time.sleep(1)
        except:
          print("Invalid number")
          time.sleep(1)
        deleteScreen()
      else:
        mainScreen()
    def saveList():
      f = open("Your_shopping_list.txt", "w")
      for item in sl:
        f.write(item)
        f.close()
      mainScreen()
#This is what happens if the user chooses Option 1
#This is the part that calculates the value of up to 10 products
  if option == 1:
#This notifies the user that there can only be up to 10 product sizes entered
    print("Please note: This code can only take up to 10 product sizes.")
#This asks the user how many products there are
    products = int(input("How many products are there? "))
#This is just in case the user still types that there are over 10 products
    if products > 10:
      print("This code can only take up to 10 product sizes.")
      print("Please enter only up to 10 product sizes below.")
    if products <= 1:
#This tells the user that they must enter at least 2 product sizes to compare them
      print("You must enter at least two product sizes to compare.")
    if products >= 1:
#This asks for information because the user may just be looking for the $/g.
      cost1 = float(input("Cost of first product($): "))
      mass1 = float(input("Mass of first product(g): "))
      ans1 = cost1/mass1
      a = ans1
#This part substitutes undefined variables with a blank
#This is in case the number of sizes being compared doesn't reach 2 to 10
      ans2 = ""
      ans3 = ""
      ans4 = ""
      ans5 = ""
      ans6 = ""
      ans7 = ""
      ans8 = ""
      ans9 = ""
      ans10 = ""
#This is for when there are two or more product sizes
    if products >= 2:
      cost2 = float(input("Cost of second product($): "))
      mass2 = float(input("Mass of second product(g): "))
      ans2 = cost2/mass2
      if a > ans2:
        a = ans2
#This is for when there are three or more product sizes
    if products >= 3:
      cost3 = float(input("Cost of third product($): "))
      mass3 = float(input("Mass of third product(g): "))
      ans3 = cost3/mass3
      if a > ans3:
        a = ans3
      ans4 = ""
      ans5 = ""
      ans6 = ""
      ans7 = ""
      ans8 = ""
      ans9 = ""
      ans10 = ""
#This is for when there are four or more product sizes
    if products >= 4:
      cost4 = float(input("Cost of fourth product($): "))
      mass4 = float(input("Mass of fourth product(g): "))
      ans4 = cost4/mass4
      if a > ans4:
        a = ans4
      ans5 = ""
      ans6 = ""
      ans7 = ""
      ans8 = ""
      ans9 = ""
      ans10 = ""
#This is for when there are five or more product sizes
    if products >= 5:
      cost5 = float(input("Cost of fifth product($): "))
      mass5 = float(input("Mass of fifth product(g): "))
      ans5 = cost5/mass5
      if a > ans5:
        a = ans5
      ans6 = ""
      ans7 = ""
      ans8 = ""
      ans9 = ""
      ans10 = ""
#This is for when there are six or more product sizes
    if products >= 6:
      cost6 = float(input("Cost of sixth product($): "))
      mass6 = float(input("Mass of sixth product(g): "))
      ans6 = cost6/mass6
      if a > ans6:
        a = ans6
      ans7 = ""
      ans8 = ""
      ans9 = ""
      ans10 = ""
#This is for when there are seven or more product sizes
    if products >= 7:
      cost7 = float(input("Cost of seventh product($): "))
      mass7 = float(input("Mass of seventh product(g): "))
      ans7 = cost7/mass7
      if a > ans7:
        a = ans7
      ans8 = ""
      ans9 = ""
      ans10 = ""
#This is for when there are eight or more product sizes
    if products >= 8:
      cost8 = float(input("Cost of eighth product($): "))
      mass8 = float(input("Mass of eighth product(g): "))
      ans8 = cost8/mass8
      if a > ans8:
        a = ans8
      ans9 = ""
      ans10 = ""
#This is for when there are nine or more product sizes
    if products >= 9:
      cost9 = float(input("Cost of ninth product($): "))
      mass9 = float(input("Mass of ninth product(g): "))
      ans9 = cost9/mass9
      if a > ans9:
        a = ans9
      ans10 = ""
#This is for when there are ten or more product sizes
    if products >= 10:
      cost10 = float(input("Cost of tenth product($): "))
      mass10 = float(input("Mass of tenth product(g): "))
      ans10 = cost10/mass10
      if a > ans10:
        a = ans10
#There's nothing for 10+ sizes for there is no loop for it'll make the code too long
#This tells the user the which product size(s) is/are the ones with the best value
#This tells the user the final result
    if products >= 1:
      print("The product(s) with the best value is/are the below product number(s):")
      if ans1 == a:
        print(1)
      if ans2 == a:
        print(2)
      if ans3 == a:
        print(3)
      if ans4 == a:
        print(4)
      if ans5 == a:
        print(5)
      if ans6 == a:
        print(6)
      if ans7 == a:
        print(7)
      if ans8 == a:
        print(8)
      if ans9 == a:
        print(9)
      if ans10 == a:
        print(10)
#This tells the user the cost per gram of the product(s) with the best value is/are
      print("The cost per gram is $", a, "/ g")
#This tells the user to pick the size with best quality if multiple are above
#Sometimes, items with the best value may not have the best quality.
      print("If there are multiple options above, choose the one with best quality.")
#This is what happens if the user chooses Option 2
#This calculates the price after a discount
  if option == 2:
#This asks for the ticket (original) price of a specific product
    p = float(input('The ticket (original) price($): '))
#This asks for the discount (in percentage) of a specific product
    d = float(input('The discount(%): '))
#This then puts the information together and calculates the discount...
    s = (d*0.01)
    ps = (p*s)
    answer = (p - ps)
    answer2 = str(round(answer, 2))
    print('The discount is $', ps)
#... and also the final discounted price.
#Finally, it tells the user the result
    print('The final price is $', answer2)
#This is what happens if the user chooses Option 3
#This calculates the discount (in percentage)
  if option == 3:
#This collects information about what the ticket (original) price was
    o = float(input('The ticket (original) price($): '))
#This asks what the price of the product after the discount is
#Then it takes all the information, puts them together and calculates the discount(%)
    d = float(input('Price after the discount($): '))
    p = 100/(o/d)
    p = str(round(p, 2))
#Finally, it tells the user the result
    print('The percentage discount is', p,'%')
#This is the final option, which is for the user to quit using this application
  if option == 5:
#This asks the user one last time in case they accidentally pressed 5.
    exit = input("Are you sure you want to exit? (Yes/No): ")
#There are three versions of "Yes" to make the application more user-friendly
    if exit == "yes":
#"Thank you and goodbye" thanks the user for using this application
#Then, it says goodbye and ends the application
      print("Thank you and goodbye!")
      cont = 'no'
    if exit == "Yes":
      print("Thank you and goodbye!")
      cont = 'no'
    if exit == "YES":
      print("Thank you and goodbye!")
      cont = 'no'
#But if exit doesn't equal "Yes" or "yes" or "YES", then cont still equals "yes".
#And if cont = "yes", then the loop restarts.
#This is if the user doesn't choose any of the above and enters an invalid input
  elif option != 1:
    if option != 2:
      if option != 3:
        if option != 4:
          if option != 5:
            print('Invalid input')
#This asks if the user would like to continue or quit
            cont = input('Continue? (Yes/No): ')
#To make the application more user-friendly, there are again three versions of "No"
            if cont == 'No':
#"Thank you and goodbye" thanks the user for using this application
#Then, it says goodbye and ends the application
              print("Thank you and goodbye!")
            if cont == 'no':
              print("Thank you and goodbye!")
            if cont == 'NO':
              print("Thank you and goodbye!")