Download CIS_103_Programming_Concepts_Overview

CIS 103 - Computer Programming Logic
Programming Concepts
Overview
prepared by Jack Wilson
Cerritos College
Property of Jack Wilson, Cerritos College
1
Topics
1.1
1.2
1.3
1.4
1.5
1.6
1.7
1.8
1.9
Programs
Modules
Algorithms
Statements
Syntax & Semantics
Logic Planning Tools
Control Structures
Memory Concepts
Data Types
Programming Concepts Overview
Property of Jack Wilson, Cerritos College
2
1.1 Programs
A program contains one or more
modules.
Program
module
module
Many languages require a module with a special name, such as
"main" for a program to be created.
Programs are often also referred to as applications or more
generally as software.
Programming Concepts Overview
Property of Jack Wilson, Cerritos College
3
1.2 Modules

A module is a collection of statements that
perform a specific task within a program.

Module is a generic term. The most
commonly used terms are listed below.


function
method
Programming Concepts Overview
C, C++, Python
Java
Property of Jack Wilson, Cerritos College
4
1.3 Algorithms
An algorithm is the name given to the
logic that is developed and used to code
the statements in a module.
Algorithm to square a number:
1. get a number
2. multiply the number by itself
3. return this value
Programming Concepts Overview
Implementation of the algorithm
in a module (function):
double square ( double number )
{
return number * number;
}
Property of Jack Wilson, Cerritos College
5
1.4 Statements

A statement is the name given to a high level
language instruction.

Programs are written using a variety of different
types of statements. Examples include:





Declaration
Assignment
Input
Output
Module Invocation
Programming Concepts Overview
int count
count = 0
get(number)
put(“Grand Total is “ + total)
printHeadings()
Property of Jack Wilson, Cerritos College
6
1.5 Syntax & Semantics

Syntax refers to the rules of a language that must be
followed to construct a valid statement. Statements
are constructed using the following components:






reserved words ( aka keywords )
identifiers
operators
literals
punctuation symbols
Semantics refers to the meaning of a statement. It
addresses the question "What does the statement
do?“.
Programming Concepts Overview
Property of Jack Wilson, Cerritos College
7
1.6 Control Structures
A control Structure determines the flow of
execution for statements executing in a
module.
There are 3 control structures that are
used in all programming languages:
1. Sequence
2. Selection
3. Repetition (aka Iteration)
Programming Concepts Overview
Property of Jack Wilson, Cerritos College
8
1.6 Control Structures
Sequence Structure
A sequence structure
performs a single task
without asking any questions
or repeating anything.
•
•
•
•
•
•
•
declare a variable
assign a value to a variable
input a value
output a value
call a function
return a value from a function
stop program execution
Programming Concepts Overview
Property of Jack Wilson, Cerritos College
9
1.6 Control Structures
Selection Structure
Asks a question (called a
condition) and based on the
answer ( true or false ) follows
a path of execution.
In example 2, only one of the
paths of execution would be
followed.
false
true
Example 1 – One path of execution
false
The
rectangle
represents
a structure.
true
The diamond symbol
represents a condition that
evaluates to true or false.
Example 2 – Two paths of execution
Programming Concepts Overview
Property of Jack Wilson, Cerritos College
10
1.6 Control Structures
Repetition Structure
true
Asks a question (called the
condition) and based on the
answer ( true or false ) executes
a statement or exits the
structure.
false
Example 1: Pre-test loop
The rectangle
represents a
statement.
Continues to execute the
statement as long as the
condition evaluates to yes.
true
A repetition structure is often
called a "loop".
The diamond
represents a
condition.
false
Example 2: Post-test loop
Programming Concepts Overview
Property of Jack Wilson, Cerritos College
11
1.7 Logic Planning Tools





Pseudocode
Flowchart
Hierarchy Chart
Printer/Screen Spacing Chart
File Description (record layout chart)
Programming Concepts Overview
Property of Jack Wilson, Cerritos College
12
1.8 Memory Concepts

Memory is measured in bytes ( KB / MB / GB / TB )

A byte is 8 bits ( binary digits )

Every byte in RAM memory is assigned a unique
address

Data types use one or more bytes to store
information
integer – 4 bytes
Programming Concepts Overview
real number – 8 bytes
Property of Jack Wilson, Cerritos College
13
1.8 Memory Concepts

To avoid having to reference a specific location in memory to
access a piece of data, variable names are used instead of
addresses. To use a variable in a program, you must declare the
variable by giving it a name and a data type.
[ RAPTOR does not require us to do this ]
Examples:
int count

boolean finished
string name
When a program is executed, a symbol table ( think of it as a data
dictionary in memory ) is created that maps the name of a variable
to the location in memory where the data is being stored.
Programming Concepts Overview
Property of Jack Wilson, Cerritos College
14
1.9 Data Types
Programs work with data ( information stored in locations in memory ).
There are many different categories of data.

Numeric



integer numbers
real numbers
Here are some examples:
Language
Numeric
Text
Boolean
Java
int
long
float
double
char
String
boolean
C++
int
long
float
double
char
string
bool
Text



Every language has specific keywords which
are used to specify a data type. Not all data
types are supported in all languages.
a single character value
a "string" of characters
Boolean


True
False
Programming Concepts Overview
Property of Jack Wilson, Cerritos College
15
x.Xx Program Translation

Translators



Assembler
Compiler
Interpreter

JIT compilation
Programming Concepts Overview
Property of Jack Wilson, Cerritos College
16
Identifiers
Programming Concepts Overview
Property of Jack Wilson, Cerritos College
17
Expressions and Statements
Programming Concepts Overview
Property of Jack Wilson, Cerritos College
18
Object-Oriented Programming
Programming Concepts Overview
Property of Jack Wilson, Cerritos College
19
Procedural Programming
Programming Concepts Overview
Property of Jack Wilson, Cerritos College
20
Event-Driven Programming
Programming Concepts Overview
Property of Jack Wilson, Cerritos College
21
Reserved Words
Programming Concepts Overview
Property of Jack Wilson, Cerritos College
22
Operators



Mathematical (arithmetic)
Relational (boolean)
Logical
Programming Concepts Overview
Property of Jack Wilson, Cerritos College
23
Operator Precedence and Associativity
Programming Concepts Overview
Property of Jack Wilson, Cerritos College
24
File Input
Programming Concepts Overview
Property of Jack Wilson, Cerritos College
25
File Output
Programming Concepts Overview
Property of Jack Wilson, Cerritos College
26
Program Development
Programming Concepts Overview
Property of Jack Wilson, Cerritos College
27
Making Decisions
Programming Concepts Overview
Property of Jack Wilson, Cerritos College
28
Looping
Programming Concepts Overview
Property of Jack Wilson, Cerritos College
29
Working with Strings
Programming Concepts Overview
Property of Jack Wilson, Cerritos College
30
Arrays
Programming Concepts Overview
Property of Jack Wilson, Cerritos College
31
Classes
Programming Concepts Overview
Property of Jack Wilson, Cerritos College
32
Class Diagrams
Programming Concepts Overview
Property of Jack Wilson, Cerritos College
33
Formatted Output
Programming Concepts Overview
Property of Jack Wilson, Cerritos College
34