pseudo code possibly one of the hardest skills to get to grips with in learning a programming...

13
Pseudo Code Possibly one of the hardest skills to get to grips with in learning a programming language is developing the ability to take a problem and break it down into a sequence of programming commands

Upload: katrina-payne

Post on 30-Dec-2015

213 views

Category:

Documents


1 download

TRANSCRIPT

Pseudo CodePossibly one of the hardest skills to get to

grips with in learning a programming language is developing the ability to take a problem and break it down into a sequence of programming commands

If the task is simple …ProblemDeclare a variable to store the number of

students in a class

SolutionDim StudentCount as Integer

If the problem is complex...Devise a program that accepts monetary values

from payments. The payments represent part payment of money repaid against multiple loans. As the repayments come in, the oldest loan should be paid off first. Once the oldest loan is paid off the next oldest will be paid off, and so on until the most recent loan is paid. Any loans not paid off within an agreed time will require a reminder letter to be generated to the customer. After two reminders legal action will be taken.

Why is it more difficult to code compared to the first example?The problem is complexThere is no obvious 1 to 1 relationship

between the problem and the codeThe terminology of the problem is not always

clear on the first read and will almost certainly need clarification

You may not be sufficiently familiar with the programming language to know where to begin

“Find the SCORE with the problem” Sequence your tasks Choose your options Once may not be enough Recycle and reuse Evaluate and improve

Sequence your tasksWe have already seen the code for adding

a new swap

We shall take another look at it adding a break point to see the code working

Choose your options A good example to see this at work is the

login process on default.aspx

Once may not be enoughRepetition or looping is an important feature of

any programming language

To see this working we shall look at the code for the search button on the main page

The looping is in the sub procedure ListMySwaps

Recycle and reuseSplitting the code into sections called procedures makes

our life a lot simpler

Take a look at the sub procedure ManageInterface on the main page

Try deleting the sub procedure and see what happens when you run the program

Also look at the function procedure LoginValid

Note the difference between a sub procedure and a function procedure!

Evaluate and improve Refine and improve means that we go through

our logic over and over again until we think we have identified all of the steps.

It is rare to get it right on the first attempt

Pseudo CodeOne big problem when learning a language is

that as a novice you will not be familiar with the code to know how to perform certain tasks and what is possible.

 The best place to start with a coding problem

is to write out the steps in your own words.

Code TemplatesThese have been created to help you start

thinking about the structure for your code

'Step 1. write a description of what the code will do.'Step 2. list the inputs'Step 3. list the outputs 'Step 4. declare variables for inputs run and test'Step 5. declare variables for outputs run and test go to step 6'Step 6. assign values to the input variables run and test go to

step 7'Step 8. processing to go here develop and refine 'Step 7. assign output(s) to destination(s) run and test go to step 8

QuestionsBelow is a section of pseudo code for a function that will look up the name of a

person making an offer on a swap. Your task is to think about the logic for this task and put the lines of code into the correct order.