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vendredi 1 juillet 2016

PASCAL - Lesson 3

PROGRAMMING PASCAL

LESSON 2


Now we will focus on operations and strings
We will learn also IF statement
Let's start

We will make a calculator using Pascal
IF statement looks like this
if -condition- then
begin
     operations...
end;

But if there is many conditions
it will look like this

if -condition- then
begin
   operations...
end
else if -condition2- then
begin
   operations...
end
.
.
.
else -other conditions- then
begin
   operations...
end;


*** CALCULATOR ***
program calc;
uses wincrt;
var x,y,res:integer;
      sel:char;

BEGIN
    writeln('1. Addition');
    writeln('2. Substraction');
    writeln('3. Multiplication');
    writeln('    Select: ');Readln(sel);
write('Enter an integer a=');readln(a);
write('Enter an integer b=');readln(b);
if sel='1' then res=a+b
else if sel='2' then res=a-b
else if sel='3' then res=a*b
else write('Invalid number.');
end.





Pascal - Lesson 2

PROGRAMMING PASCAL

LESSON 2


In this lesson we will learn variables integer; real; char; string...
Example:
Integer: 25 4 -2 3 85
Real: 120.36 -9.66 45.12
Char: A B C D E f g h i j k l
String: PASCAL programming Hello

we put variables after uses wincrt line.
Example var Num1,Num2:Integer;

Integers have ranges limits and types










Reals also have types:

You can use Real or Double.


Operators in Pascal
+ Addition
- Substraction
* Multiplication
/ Division (Integer/real result)
DIV Division (Integer result)
MOD Division (Integer result the rest of division)
> Superiour
< Inferiour
   <> Differnce
   = Equality

When we use variables we use in the main program readln to read the varible
Example

program test;
uses wincrt;
var Num1:Integer;
begin
write('Enter an integer');
readln(Num1);
write(Num1);
end.

Pascal - Lesson 1

PROGRAMMING PASCAL

LESSON 1


We will begin with simple programs. We begin with 'Hello World' program.


As any languages has rules, grammar, syntax... Pascal has his own rules and you should obey it.


The program name we write (program myfirstprog)we use begin in the program beginning and end on its ending
but before that we write uses means using a library like wincrt which allow writing and reading variables.
after we put BEGIN we want to show this message on computer screen "Hello World"so it will be like that write('Hello world');this is a line each line ends with ;
The program will be like this:


program myfirstprog;

uses wincrt;
BEGIN
         write('Hello World');
END.

I think Pascal is the easiest programming language

Install Pascal 
here