Psuedocode and Flowcharts assignment

Although we may be late to the game, we will nevertheless join the world of e-commerce to sell our fantastic product on the Internet. To do so, we need a Web site that will allow for commerce and sales. To be quick about it, we require the following:

· Searchable inventory and shopping pages

· A shopping cart

· A place for customers to register when they make purchases

· A checkout process to make the purchase

Within this main process, there are a bunch of other needs that must be met, as follows:

· We want to track the date of the last purchase a customer make so we can offer incentives and discounts based on the last time they shopped.

· We will offer sales based on the number of different items that a person purchases.

· We will also give discounts for bulk orders a discount when a person buys many of the same item

In addition to sales feature, the solution must provide the ability to manage and research the sales of products. It must include the following:

· Must be able to add, update and remove product inventory in real time on the site

· Needs to have research capabilities to determine how well a product is selling, such as the following:

· How often the item is viewed, added to shopping carts, and then purchased

· How a price change affects sales and profit

From the description above, we can relate this to the following use cases, which describe how the user will interact with our system. Each use case is a set of screens that the users would interact with to accomplish something they need on the site.

In addition to the customer’s activity, the solution will allow Sales Analysts to manage and research product sales.

Our architects have created the following components to be realized by our development team in meeting the use cases above.

SearchEngine

ProductInventory

ShoppingCart

CardProcessing

Purchasing

CustomerManager

UserSecurity

Fill out the following table to describe which components are used by each use case and how each component will help realize the use case:

We could realize this design as either structured or Object-Oriented given the following design diagrams.

calculate OrderTotal

Calculate Subtotal

bigBuyer Discount

bulkBuyer Discount

returnCustomer Bonus

daysSinceLast Purchase

Figure 2: Sequence Diagram for calculateOrderTotal

;Order

;DiscountManager

;Customer

;Taxes

bigBuyerDiscount()

bulkBuyerDiscount()

returnCustomerBonus()

daysSinceLastPurchase()

calculateSubtotal()

Given the designs above, we need to analyze which approach we should take and how the code realization will differ.

Structure Design

· Describe the implementation of the structure design in Figure 1 and how it relates to the Checkout use case.

· What procedures and functions are being created in the design?

· What data would be passed between these procedures and functions?

Object-Oriented Design

· Describe the implementation of the object-oriented design in Figure 2 and how it relates to the Checkout use case.

· What methods are being created in the design?

· What data would be passed between these methods?

Comparison

· How do these approaches (Structured versus OO) differ?

· How much will the detailed implementation when we get to code differ because of the high level design approach we choose?

For the product research use case, take a stab at either a structured design diagram or a sequence diagram that would fulfill at least part of the functionality of the use case. We will compare what you create here to the detailed design we create through the rest of the course as a way of measuring your progress.

· Provide a diagram of your choice here to show a flow for researching products.

The exact details are flexible within the description of the functionality, so do your best to create a flow that looks like a code solution using the components above or ones you think you need. This is practice that will give you a measuring stick for your learning as we see problems later in the course related to this system.

Description

It is important to know the profit each product is providing to the bottom line. Given that we know the wholesale cost, the retail cost to consumers and the number of items we have sold, calculate the profit for a given product.

Pseudocode

function productProfit(productPrice : Double,

wholesalePrice : Double,

numberOfPurchases : Integer)

Return Double

<add your logic here>

End function

Description

Continuing with the same example of calculation product profit, utilize the same scenario to create a flowchart.

Description - It is important to know the profit each product is providing to the bottom line. Given that we know the wholesale cost, the retail cost to consumers and the number of items we have sold, calculate the profit for a given product.

Flowchart

<insert here>

Additional Pseudocode

Discuss how input/output, operators, and expressions are presented in pseduocode as well as how they are used to accommodate needs for sequential logic within business applications. Additionally, discuss how various data types may be used within sequential logic structures.

Description

We want to ensure that the system will not accidentally discount a product below the price that it is purchased for. Thus, we want an operation to ensure that, when a discount is applied, it always stays more than the original purchase price.

Sample data could include the following:

· A product at $10 with a wholesale price of $5 and a discount of 10% returning $9.

· A product at $10 with a wholesale price of $6 and a discount of 50% returning $6.

Pseudocode

function applyDiscount(productPrice : Double,

wholesalePrice : Double,

discount : Double)

Return Double

<add your logic here>

End function

Flowchart

<insert here>

Description

We want to reward customers for returning to make a purchase. To incentivize, they receive a bonus discount as by the following levels.

· Less than a week = 10%

· More than 6 months = 6%

· Otherwise, 1% for each month (consider a month to be 30 days)

Sample data for testing:

Flowchart

<insert here>

Pseudocode

function returnCustomerBonus (todaysDate : Date,

lastPurchaseDate : Date,

totalPurchaeAmount : Double)

returns double

<add your logic here>

end function

Description

A customer receives his or her discount based on his or her membership status. Preferred members receive a return member bonus, and all registered members receive a bulk discount, but guests do not receive any discounts.

This should reuse the discounts from the prior work, so test cases from there would apply. Just make sure that guests receive no discount, registered members just get a discount for any items for the bulk discount, and preferred members get both the bulk discount and the return customer bonus.

Flowchart

<insert here>

Pseudocode

function applyDiscounts (todaysDate : Date,

lastPurchaseDate : Date,

totalPurchaseAmount : Double,

membershipLevel : Integer)

returns double

<add your logic here>

end function

Description

Once the final prices are calculated for each product, we need to total up the order and then add in sales tax. We need to go through the line items in an order and figure out the final price.

Flowchart

Create variable Double: subtotal

Return calculateSubtotal (subtotal, salesTaxRate)

Subtotal = subtotal + lineItemTotal

index = each item in lineItemPrice

lineItemTotal= lineItemPrice[index] * lineItemQuantity[index]

Pseudocode

function totalOrder (lineItemPrice: Array,

lineItemQuantity : Array,

saleTaxRate : Double)

returns double

Create variable Double : subtotal

for (index = each item in lineItemPrice)

lineItemTotal = lineItemPrice[index] * lineItemQuantity[index]

subtotal = subtotal + lineItemTotal

end loop

return calculateSubtotal (subtotal, salesTaxRate)

end function

Fill in the following table by walking through the logic above. The idea is to analyze how the chart and pseudocode was created, because you will be doing this in a few minutes, so do not just jump to the easy answer. Follow the steps as if you are the computer executing the software designed.

Description

Given the list of all the product prices and wholesale prices as well as a list of all the items sold for each product calculate the net profit for all the products.

Flowchart

<insert here>

Pseudocode

function totalProfits (allProductSalesNumbers: Array,

allProductPrices : Array,

allProductWholesalePrices : Array)

returns double

<add your logic here>

end function

Description

To expand further, we want to try out logic in interacting with users. Here is a sample of a game, using loops and decisions to allow a person to play rock-paper-scissors with a computer.

Pseudocode

We have a helper function that we will use here that tells us who won. It will result in +1 if the player wins, a -1 if the computer wins, and a 0 if it is a tie.

function compareOutcome(computerMove: Integer,

playerChoice : Integer) returns Integer

And the main flow of our logic is as such.

while (true)

Integer : computerChoice = randomChooser()

Integer : playerEntry = prompt user to enter a value

If (playerEntry is not a valid input)

Prompt user they have picked a bad number and try again

Else

Integer : outcome = compareOutcome(computerMove, playerEntry)

If (outcome = 0)

Prompt user it is a tie, and try again

Else if (outcome = -1)

Prompt user they lost

Break out of loop

Else

Prompt user they won

Break out of loop

End if

End if

end loop

Flowchart

true

playerEntry is not a valid input

outcome = 0

outcome = -1

Integer : computerChoice = ramdonChooser()

Integer : playerEntry = prompt user to enter a value

Prompt user they have picked a bad number and try again

Integer : outcome = compareOutcome(computerMove, playerEntry)

Prompt user it is a tie, and try again

Prompt user they lost

Break

Prompt user they won

End of game

Break

Note: In this case, note the advantages and disadvantages of flowcharts and pseudocode. The flowchart is easy to follow the logic for one scenario, but does it make it easier or harder to understand the code as a whole? There is no strict answer, but one that tells you a bit about your way of thinking and personal preference.

Interaction Scenario

For either of the solutions above, follow the logic and map out your interaction step-by-step, trying to exercise all paths of the logic. You will have to take at least 2 times through the game to map all scenarios.

Scenario 1

Scenario 2

(copy and add more if needed/desired)

Description

Now it is your turn to try out user interaction with a simple game. This goes back to the number guessing game. The user will input a number each time, say between 1 and 100. The computer will randomly select 1 number each game (note this is different than the example above where it selects a new answer each round), and the game continues until the user guesses the right number.

Like above, your solution should accommodate for invalid input, but do not worry about how to make that logic work for now. Your solution should give some hints though if the guess the user made was too high or too low, to help them on their way.

Flowchart

<Your solution here>

Pseudocode

<your solution here>

Throughout this course, we have been realizing the detailed design for the pieces of the whole picture we started with at the beginning of the course. We have built many abstractions, so let’s go back and document what we have found and see the abstractions we have created.

Sometimes it is easy to see how the whole solution can be broken into pieces, and other times it is done as you see abstractions and opportunities for reuse in the resulting design. This is called refactoring. For the pseudocode you see below, look for abstractions you could create and create a flowchart using your simplifications.

Psuedocode in Need of Refactoring

Array : namesInSystem

Array : phoneNumbersInSystem

String : nameInput

While (nameInput is not valid)

nameInput = prompt user for input

if (nameInput is provided and not blank)

break out of loop

end loop

Prompt user the input is required and not blank

End loop

Integer : indexForName = -1

For (index = all items in namesInSystem

If (nameInput = namesInSystem[index])

indexForName = index

end if

End loop

If (indexForName = -1)

Prompt user “We cannot find your account, please call us”

Else

String : phoneNumberInput

While (phoneNumber is not valid)

phoneNumber = prompt user for input

if (phoneNumber is provided and not blank)

break out of loop

end loop

Prompt user the input is required and not blank

End loop

If (phoneNumber = phoneNumbersInSystem[indexForName])

Prompt “we found your account welcome”

Else

Prompt “we cannot validate your account, try again later”

End if

End if

Refactored Flowchart

The above pseudocode is long, but you can omit much of the details. You can accomplish the same logic removing more than 30 lines. You do not have to show all of the details removed if moved into an abstraction, simply name the abstraction and define the parameters to be passed to the call replacing the lines of code.

<insert your flowchart here>