Abdu's Computer Science - Midterm Test Review

• State and briefly explain the general steps of an SDLC model.

1. Planning: This initial phase involves Requirements Analysis to define needs, followed by the Design stage where Prototypes and Algorithms are developed. It also includes a Verification step to analyze the design before either repeating the process or moving to implementation.

2. Implementation: In this stage, programmers put the computer code together to build the software. A critical part of this phase is Testing, which involves debugging the code to find errors and ensure it executes properly.

3. Maintenance: Once the program is built, it is released for use, often undergoing beta-testing. During this final phase, the software is modified, enhanced, or corrected as needed based on how it performs in a real-world environment.

What does SDLC stand for, what is its purpose and how is it generally used?

SDLC (Software Development Life Cycle) is a step-by-step plan used to design and build quality software.

It generally consists of three stages:

• Planning: Defining requirements and creating designs like prototypes and algorithms.

• Implementation: Writing the code and testing it to debug errors.

• Maintenance: Releasing the software and modifying or correcting it based on actual use.

Organizations use specific industry models, such as Waterfall or Agile, to follow this process

What is a prototype? At what point in the SDLC is it used? What are a few things to consider when designing a prototype?

A prototype is a paper or digital model designed to show how a finished product will look and flow. It is primarily used for User Interface (GUI) design.

SDLC Phase

Prototypes are created during the Planning phase, specifically as part of the Design stage, which is considered the "true software planning" step.

Things to Consider

When designing a prototype, you should focus on the following:

• Goals: Define what the software needs to do and what its overall goal is.

• Users: Identify who your users are, what they expect from the software, and what their specific needs are.

• Testing and Feedback: Have users test the prototype so you can incorporate their feedback into the final design.

What is an algorithm? What are the 2 types of algorithms? What are some suggestions on how to write (design) algorithms?

An algorithm is a step-by-step general plan or design for a software solution.

The Two Types of Algorithms

1. Pseudocode: A detailed algorithm written in "broken English" using common programming structures that looks similar to a coded program.

2. Flowchart: A visual representation of a detailed algorithm that uses specific "Lego brick" shapes and arrows to show the program's flow.

Suggestions for Designing Algorithms

• Be Precise: Define all inputs and outputs precisely and make every step clear and unambiguous.

• Keep it "High Level": An algorithm should be a "bird's-eye view" rather than a microscope; it should be written in a "language-agnostic" way so it can be translated into any programming language instead of being actual computer code.

• Use Proper Symbols: When creating flowcharts, use the correct shapes (like ovals for Start/Stop and diamonds for Decisions) and always label the paths coming out of a decision as "True/False" or "Yes/No".

What are 3 possible "clauses" (sections/blocks) of the exception handling structure? Name them and give a one point/sentence explanation for each one.

1. try: This block contains the specific code you want to attempt to run.

2. except: This code executes only if the instructions in the try block result in an error or exception.

3. else: This block runs only if no errors or exceptions occur during the execution of the try block.