Introduction To C++ Programming 1.0 Basic C++ Program Structure 2.0 Program Control 3.0 Array And...

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FP201 Programming Fundamentals

•Introduction To C++ Programming1.0•Basic C++ Program Structure2.0•Program Control3.0•Array And Structures4.0•Function5.0•Pointer6.0•Secure Programming in C++7.0

FP201 PROGRAMMING FUNDAMENTALS

© 2011/2012 | PN NORHASLIZA BT MUHAMAD NOR

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2.0 BASIC C++ PROGRAM STRUCTURE

2.1 Understand The C++ Program Basic Structure


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LEARNING OUTCOMES TOPIC 2.1

• Explain the functionality of each item in C++ program structure 1

By the end of this chapter students shall be able to :



// my first program in C++ #include <iostream> using namespace std; int main ()

{cout << "Hello World!“<<endl;

return 0; }

comment

PreprocessorDirectives

Main function

braces

output

Return statement

Header file

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C++ PROGRAM STRUCTURE



a) Preprocessor Directives▫such as #define , are typically used to make source

programs easy to change and easy to compile. Directives in the source file tell the preprocessor to perform specific actions.

▫Example:

#define LENGTH 10 var = LENGTH * 20;

FUNCTION OF THE STRUCTURE

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b) Header Files▫.h files or "headers" are libraries of code you may

insert in your program by including them by reference in the top block.

▫Example:#include< stdio.h >#include< iostream.h >

Cont…

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•The point of header files is to create libraries of code that can be used over and over▫#include< stdio.h > is the Standard Input and Output

header file. Expl : printf, scanf.▫#include< iostream.h > is the Input and Output Stream

header file. Expl : cout, cin.

Cont…

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•Types of Header Files (cont’)

1. iostream.h -Input/Output, interaction with the program. Expl : getline.

2. math.h –For using mathematic formula 3. string.h- C++ has no built-in string handling. Use this

library to copy strings, find string length, etc. 4. stdio.h- Similar to stdlib but also has some file

functions. printf, scanf(for C language)

Cont…

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http://www.cplusplus.com/ref/iostream/iostream/

http://www.cplusplus.com/ref/iostream/fstream/

http://www.cplusplus.com/ref/cstring/

http://www.cplusplus.com/ref/cstdio/

c) Main Function• Is the place where the code execution begins.

int main() { return 0;}

Cont…

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void main() { }

d) Return Statements•Terminates the execution of a function and returns

control to the calling function (or, in the case of the main function, transfers control back to the operating system). Execution resumes in the calling function at the point immediately following the call.

Cont…

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2.2 Classify Identifier and Keyword FP201 PROGRAMMING FUNDAMENTALS

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• Explain identifier, variable and constant.

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• State the naming convention rules for identifier.

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•Declare variables and constants. 3

•Initializes variables 4

•Determine identifier scope: local, global. 5

•Explain keywords6




• Identifier : A name associated with a variable and constant, usually limited to letters,digits and underscores.

•Variables are identifiers whose value may change during the course of execution of a program.

•Variable represent memory location where you can store value such as characters, numbers and pointers.

•Constants are identifiers whose value is kept permanently for program to use

•Remain unchanged throughout a program

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IDENTIFIER, VARIABLE AND CONSTANT



1. Identifiers must begin with a letter or underscore. ▫Only letters(A-Z,a-z), digits(0-9), or underscore( _ ) may

follow the initial letter. ▫Ex: sum_of_squares, box_22A, GetData

2. The blank space cannot be used. ▫Ex: Get Data cannot be an identifier as blanks are not

allowed in identifiers

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NAMING CONVENTION RULES FOR IDENTIFIER



3. Identifiers cannot be reserved words. Reserved words or keywords are identifiers reserved for system use. ▫Ex: int......cannot be an identifier as it is a reserved

word in C++

4. Identifiers beginning with an underscore have special meaning in some C++ systems, so it is best not to start your identifiers with an underscore.

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Cont..



5. Most C++ compilers will recognize the first 32 characters in an identifier.

Also, C++ is a case sensitive language. C++ will distinguish between upper and lower case letters in identifiers. Therefore:

grade and Grade are different identifier

6. Avoid excessively long identifiers.

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Cont..



7. You can develop your own conventions like below: ▫A single word identifier will be written in lower case

only. Examples: grade, number, sum.

▫If an identifier is made up of several words, the first letter will be lower case. Subsequent words will begin with upper case. Some examples are: stringType, passingScore, largestNum.

▫Identifiers used as constants are often fully capitalized. Examples: PI, MAXSTRLEN.

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Cont..



•A C++ variable is declared by telling the program:▫the data type to be used ▫the name of the variable▫Syntax : dataType variableName;▫Examples:

int Marks;Data Type Variable

DECLARE VARIABLES AND CONSTANT

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•To declare more than one variable of the same data type.

• For example:

int a, b, c;

Cont..

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•Constants are expressions with a fixed value.▫To declare constant (#define) :

#define constName value

For example:

#define PI 3.14159

Cont..

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▫To declare constant (const)

▫Syntax:const dataType constName = value;Example:

const int PATH = 100;

Cont..

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• It is done by appending an equal sign followed by the value to which the variable will be initialized:

type identifier = initial_value ;

For example, :

int a = 0;

INITIALIZE VARIABLES

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•A variable can be either of global or local scope. •A global variable is a variable declared in the main

body of the source code, outside all functions, while a local variable is one declared within the body of a function or a block.

LOCAL AND GLOBAL VARIABLES

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Cont..

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#include<iostream.h>

int main(){

int a; // This is a variable

int calArea(int b,int c); //This is a function declaration

cout << "Please enter a value : ";cin >> a;

return 0;}

Global variable

Localvariable

•Keywords are predefined reserved identifiers that have special meanings.

•They cannot be used as identifiers in your program.•Example:

▫void▫main▫float

KEYWORD

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2.3 Classify Data Types FP201 PROGRAMMING FUNDAMENTALS

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• Explain the basic data types: char, int, double, float, bool 1




1. int:• is used to declare integers, whole numbers either

positive or negative. The following statement shows how the variables of int type are declared.

int var1; int b = 10;

BASIC DATA TYPES

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2. long:• This long keyword is used for declaring longer

numbers. 3. float:• This keyword float is used to declare floating point

decimal numbers. A sample declaration would be:

float var2; //Sample declaration for floator float var2 = 2.34;

Cont…

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4. char:• This keyword is used to declare characters. The

characters that can be used with this data type are ASCII characters.

char a[9]=“Malaysia”; char a[]=“Malaysia”;

char noPhone[11]=“0134022331”;

Cont…

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5. String:• Must include header file string.h

#include <iostream.h>#include <string.h>

Int main(){

………..string mystring = "This is a string";……return 0;

}

Cont…

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6. Boolean•To declare a boolean variable, we use the keyword bool.

bool bValue;

•When assigning values to boolean variables, we use the keywords true and false.

bool bValue1 = true;

Cont…

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2.4 Use Input Output Statements FP201 PROGRAMMING FUNDAMENTALS

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• Identify the syntax use for input and output.1

• Write algorithm and programs that use the input and output statements.2


F2037 PROGRAMMING FUNDAMENTALS WITH C++


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• Use cin >>• Must have header file iostream.h

#include <iostream.h>void main(){int n1, n2, n3;cout << "Enter 3 numbers : ";cin >> n1 >> n2 >> n3;

}

INPUT STATEMENTS



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#include <iostream.h>void main(){int n1, n2, n3;cout << "Enter 3 numbers : ";cout << “First Number : ";cin >> n1 ;cout << “Second Number : ";cin >> n2 ;cout << “Third Number : ";cin >> n3 ;

}

INPUT STATEMENTS



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• Use cout <<• Must have header file iostream.h

#include <iostream.h>void main(){int n1, n2, n3;cout << "Enter 3 numbers : ";cin >> n1 >> n2 >> n3;

}

OUTPUT STATEMENTS



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#include <iostream.h>void main(){int n1;cout << "Enter 1 numbers : ";cin >> n1 ;cout << “The number you enter : “<< n1;

}

OUTPUT STATEMENTS



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2.5 Apply Operators & Expression


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• Explain Arithmetic , Assignment, Increment & Decrement, Relational and logical Operator

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• Explain operators precedence 2

• Write expression using operator3

• Use expression in program4




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• The five arithmetical operations supported by the C++ language are:

+ addition - subtraction * multiplication / division % modulus

ARITHMETIC OPERATOR



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a=5value+= increase value = value +

increase; a -= 5 a = a - 5; a /= b a = a / b; price *= units + 1 price = price * (units

+ 1);

• Refer to the symbol (=),equal.• 1)Use to give the value to variable• 2)or to modify the value of a variable by performing an operation

on the value currently stored in that variable :

ASSIGNMENT OPERATOR



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1)Operasi Unari Prefix

2)Operasi Unari Postix

a ++;a --;

++ a; -- a;

Cth :int x = 180, y =200;y= x++;cout<<“x:”<<x<<endl<<“y:”<<y<<endl;

Output: x : 181y : 180

Cth :int x = 180, y =200;y= ++x;cout<<“x:”<<x<<endl<<“y:”<<y<<endl;

Output: x : 181y : 181

INCREMENT & DECREMENT OPERATOR



Operator Meaning Example

== Equal to 4 = =4

< Less than 2 < 7

> Greater than 8 > 3

<= Less than or equal to 6 < = 7

>= Greater than or equal to 13 > = 5

!= Not equal to 6 != 2

RELATIONAL OPERATOR

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Assignment and Relational operators

= is not the same as the operator

==assigns the value at its right to the variable at its left

the equality operator that compares whether both expressions in the two sides of it are equal to each other



X Y x or y||

x And y&&

Not x

True True True True False

True False True False False

False True True False True

False False False False True

LOGICAL OPERATOR

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• The conditional operator evaluates an expression returning a value if that expression is true and a different one if the expression is evaluated as false. Its format is:

condition ? result1 : result2

7>5 ? 3 : 2Answer : 3

CONDITIONAL OPERATOR ?:FP201 PROGRAMMING FUNDAMENTALS


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OPERATORS PRECEDENCEFP201 PROGRAMMING FUNDAMENTALS


Introduction To C++ Programming 1.0 Basic C++ Program Structure 2.0 Program Control 3.0 Array And...

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