2.    Ask for two numbers to be typed in at the keyboard, then display the larger of the two numbers

3.    Ask for a number to be typed in at the keyboard, then display a message to say whether or not the number is within the range 0 to 100

Number functions – work out what each of these do
•    INT
•    TRUNC
•    FRAC
•    ROUND

Arithmetic Functions – work out what each of these do
•    SQR
•    SQRT
•    ABS

1. Display the message “Hello World!” 25 times
2. Change the program so that the user can decide how many times to display “Hello World” on the screen.
3. Display the number of the repetition on the screen as well (eg. 1. Hello World!, 2. Hello World!, etc.)
4. Ask the user which times table they wish to see, then display it in the following format:
   1 * 7 = 7
   2 * 7 = 14
   .
   .
   12 * 7 = 84
5. Ask the user how many stars they want to see in one row. Display the row of stars
6. Expand your solution and ask the user how many rows of stars they want to see. Display the rectangle of stars as specified by the user. Hint – you will need to nest one For loop inside another!

While Loops

1. Ask the user to enter a whole number greater than 99. If the user enters a number less than 100, display an error message and ask them again. Repeat this process until the user enters a valid number.
2. Expand your solution to only accept numbers between 100 and 200

Repeat Loops

1. Add up a series of whole numbers entered by the user, until the user enters zero.
2. Expand your solution to display the average value of the numbers entered. Hint: do not count the final zero as a value to be averaged.
   

The majority of programs that you make in pascal will always follow the below format, it is first typed into the compiler when making your program:

program ProgramName;

{$APPTYPE CONSOLE}

uses SysUtils;

begin

end.

You would write a meaningful program named where I wrote “ProgramName” as to tell the person who is reading your source code, what the program does. Then perhaps a comment afterwards to describe what purpose your program serves.

Between “begin” and “end.” is where you write the main part of your program. Below is an example of a simple program which would display “Hello World” on the screen.

program HelloWorld;
{a program which displays "hello world" on the screen }

{$APPTYPE CONSOLE}

uses SysUtils;

begin
             {the code that displays Hello World! on the screen}
             writeln('Hello World');
end.

Try it out in your compiler to see how it works.

1. First Program
2. Effective Use of Comments
3. Variables
4. Declaration
5. Input & Output
6. Assignment
7. Operators

- to be edited -

NumberOne := 9;

We read the above as: “NumberOne becomes equal to 9″. The assignment can also consist of an expression, a formula. And then the value or outcome of that expression is stored in the variable. For example, the value of 6 is stored in a variable named “NumberOne” and 5 in “NumberTwo”. What would be the value of “Sum” in the following example?

Sum := NumberOne + NumberTwo;

The value of “Sum”, would of course be 11. For more information on operators please click here.

Declaring variables
Above any instructions which you write, you first need to include the declaration block where you will declare all of your variables. Below is the basic layout of a complete program:

program
{program name here}
uses
{library which pascal uses}
const
{constant declaration block}
var
{variable declaration block}
function
{any functions that are used}
procedure
{any procedures that are used}
begin
{start of main program block}
end.
{end of main program block and program}

The next example shows an exemplar declaration block which declares three variables:

var
     number1, number2  : integer;
     myPhrase          : string;

As in the example above, variables sharing the same data type can be separated by commas and after the variable(s) comes a colon which is followed by the data type. It is also good practice to align up all colons and then data types respectively for easing reading.

If you declare variables, as in the above layout of a complete program, in the variable declaration block which is above any procedures or functions, these are global variables, of which can be accessed anywhere in the code. However they are not always desirable as they could be accidental changed which is why local variables exist. Local variables are declared within a routine, such as a function or a procedure.