180Daraga-

Cpp course BY: Moustafa Mohamed Ali

Mid-Year

2013/2014

1

Outline Variables, Data types , casting & I/O

Compilers and IDEs

Control Statements

Loops

Functions

Arrays & String

Structures & Files

Pointers and Dynamic allocation

Recursion

STL.

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Introduction

Why programming languages !?

That’s how we communicate with the

machines and tell the computer what to

do.

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Evolution of programming

languages

Machine code

Time consuming, very difficult

Assembly

Written for one pc and can’t run on

another

High level programming languages

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Why using C++ !?

Maintainability

Modifying code is much easier

It’s OOP

Portability

Can’t be written and compiled on any

CPU.

C++ gives you access to some lower level

functionality (Pointers , bytes ,…etc)

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Tools we will use

Eclipse (Recommended)

Codeblocks (Recommended)

Dev

Netbeans

MS c++

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Hello World

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RUN !

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IN DEEP (Libraries) !

What is iostream !?

It’s Header that defines the standard

input/output stream objects .

it has two classes istream , ostream

Cout it’s an object from the class ostream << it’s called insertion operator

Cin it’s an object from the class istream >> it’s called extraction operator

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IN DEEP (Cont.)

Namespace std Sort of directory of names.

many standard C++ identifiers are

defined

When we use it we tell the compiler to look

for any identifier we haven’t defined in

the std (Standard) namespace.

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IN DEEP (Cont.)

Int main () The program needs to know from where to

start executing the program, the main

function is the starting point

Return 0 It’s a value that tells the operating system

that this program executed successfully

with no errors

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IN DEEP (Cont.)

(int argc, char** argv) They are called parameters and they will

be discussed next sessions (functions

session )

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Important rules

Semi-colon “ ; “

It’s tell the compiler that this line of code is

finished

Cin takes this operator >> , while Cout

takes this operator <<

Write a readable code

Use tabs

Don’t forget brackets … etc

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Compiler VS IDE

Compiler

It’s a program that transform from high level

languages to machine code to let the CPU

understands what you wrote, computers

doesn’t know but 0’s and 1’s

Best compiler is GNU

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Compiler VS IDE (Cont.)

Integrated development environment it

provide the developer a set of features

like

Source code editor

Debugger

Intelligent code completion

Eclipse , NetBeans , Dev ….

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Compilation process

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Compilation process (Cont.)

Preprocessor

It processes include-files , replace the #include with the content

Compiler

Output an incomplete object code (machine code, binary form 0’s and 1’s)

Linker

Linking refers to the creation of a single executable file from multiple object files.

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Compilation process (Cont.)

In C++, all these steps are performed

early, before you start running a

program. In some other languages, they

are done during the execution

process, which takes time. This is one

of the reasons C++ code runs far

faster than code in many more recent

languages.

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Data Types

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How to declare a variables !?

A variable in C++ is a name for a piece of

memory that can be used to store information

DataType Variablename ;

Int x ;

Double y ;

Char c ;

Variables names can’t begin with numbers,

can’t be reserved in the langauge it self like

(return , int , double ..etc)

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Variables

We can initialize it by setting a value using

assignment operator “=”

Int x = 5

Char y = ‘n’

….etc

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Inputs

We can take inputs from user by using

cin>>variable name

Cin>>x;

Cin>>mychar ;

….etc

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Outputs

We can print the value of the number by

using the cout << variable name

Cout<<x;

Cout<<myChar ;

….etc

Note that cout<<“x” will print x on the

console

Cout<<x; it will print the value of x

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How to write a code !?

Think in very primitive way . What do I

want to do ? What do I need?

Don’t start writing code unless you know

what you will write

We tell computers to do what we want

they are stupid but very fast

Write readable code, organized sothat

you can trace it

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Practice

Write a program that takes from the user

his age and print it

Write a program to takes from the user his

gender and print it (M: Male , F:Female)

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Readings

More about compilation process

http://faculty.cs.niu.edu/~mcmahon/CS241

/Notes/compile.html

How to design a program!?

http://www.learncpp.com/cpp-tutorial/1-

10a-how-to-design-your-first-programs/

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Questions

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