algorithms and flow charts l.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
Algorithms and flow charts PowerPoint Presentation
Download Presentation
Algorithms and flow charts

Loading in 2 Seconds...

play fullscreen
1 / 34

Algorithms and flow charts - PowerPoint PPT Presentation


  • 162 Views
  • Uploaded on

Algorithms and flow charts. Prepared by Department of Preparatory year. Programming language. Programming language is an artificial language that specifies instruction to be executed on a computer. There are two types of programming languages: Low level languages High level languages.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Algorithms and flow charts' - vesta


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
algorithms and flow charts

Algorithms and flow charts

Prepared by

Department of Preparatory year

programming language
Programming language
  • Programming language is an artificial language that specifies instruction to be executed on a computer. There are two types of programming languages:
    • Low level languages
    • High level languages

Prepared by Department of Preparatory year

low level languages
Low level languages
  • A language that is machine-dependent and/or that offers few control instructions and data types. Each statement in a program written in a low-level language usually corresponds to one machine instruction.

Prepared by Department of Preparatory year

computer languages
Computer Languages:
  • The language which consists of a set of commands, understandable by computer directly or after translating, is known as computer programming language.

Prepared by Department of Preparatory year

computer languages5
Computer Languages:
  • There are many types of computer languages, which can be categorized into the following four types:-
    • Low-Level Languages (1st & 2nd Generation Languages)
    • High-Level Languages (3rd Generation Languages)
    • User-Friendly Languages (4th Generation Languages)
    • Object-Oriented Languages (5th Generation Languages)

Prepared by Department of Preparatory year

computer languages6
Computer Languages:
  • Low-Level Language:

Languages, which computer can understand directly and are machine dependent are called Low-Level Languages.

For Example:

Machine Language & Assembly Language.

Prepared by Department of Preparatory year

computer languages7
Computer Languages:
  • High-Level Language:

The languages, which computer cannot understand directly and are not machine dependent are called High-Level Languages. Some of the high-level languages are:-

    • BASIC (Beginners All Purpose Symbolic Instruction Code)
    • COBOL (Common Business Oriented Language)
    • FORTRAN (Formula Translator)
    • C etc.

Prepared by Department of Preparatory year

computer languages8
Computer Languages:
  • User-Friendly Languages:

These languages are very easy to codify and simplest to learn. Some of the common user-friendly languages are:-

    • dBASE
    • FoxPro
    • Oracle
    • MS Access
    • Sybase etc.

Prepared by Department of Preparatory year

computer languages9
Computer Languages:
  • Object-Oriented Languages:

The languages which are based on object oriented programming (OOP) approach are called as Object-Oriented languages. For example:-

    • Smalltalk
    • C++
    • Object COBOL
    • JAVA
    • Simula etc.

Prepared by Department of Preparatory year

language translators
Language Translators:
  • The software, which converts the codes of other languages into machine code are called Language Translator.
  • Language Translators are categorized into three types:-
    • Assemblers
    • Interpreters
    • Compilers

Prepared by Department of Preparatory year

language translators11
Language Translators:
  • Assembler:

Assembler translates the assembly language code (source program) into machine language code (object program). After assembling, a linker program is used to convert the object program into an executable program. The Microsoft assembler program (MASM) & Borland Turbo assembler program (TASM) are two popular assemblers. Assemblers are used mainly in development of system software.

Prepared by Department of Preparatory year

language translators12
Language Translators:
  • Interpreters:

Interpreters translate the high-level language code into machine language code, command by command. They are very slow for executing large programs, so interpreters are not suitable for most of applications development.

Prepared by Department of Preparatory year

language translators13
Language Translators:
  • Compilers:

As contrast to interpreters, compilers provide faster execution speed. Compilers translate the entire program (source code) into machine code (object code). By using linker, the object code is converted into executable code. Compilers are widely used in translating codes of high level languages. As compared to assemblers or interpreters, compilers are preferred in development of application software.

Prepared by Department of Preparatory year

main operation of high level language program
Main operation of high level language program
  • Input operations:
    • Like input, read
  • Output operations;
    • Like write, print
  • Arithmetic operations:
    • Like add, subtract, multiply etc....
  • control transferring operations:
    • Like “GO TO”, conditional, non-conditional etc....
  • Looping:
    • Like repeat, do while, for, etc...

4

Prepared by Department of Preparatory year

main step in developing program
Main step in developing program
  • Problem understanding
  • Algorithm developing
  • Program writing
  • Program editing
  • Program compiling
  • Program running
  • Testing and debugging

Prepared by Department of Preparatory year

slide16

What an Algorithm is ???

“Sequence of precise instructions which leads to a solution

is called an algorithm.”

or

“An algorithm is a set of steps that defines how a task is to

performed.”

Example:

Steps (algorithm) for preparing a cake.

Steps (algorithm) to solve a first degree equation.

Steps (algorithm) to solve a second degree equation

using delta.

Prepared by Department of Preparatory year

slide17

Example:

What is algorithm for solving a first degree equation?

1. Read the values A,B

2. Check if A=0 (if yes there is no equation) therefore no

equation to be solved (end processing).

3. Check if B=0 (if yes X=0 and end processing).

4. Calculate the value of X= -B/A

5. Print the value of : X

Prepared by Department of Preparatory year

slide18

Algorithm Representation

  • There are many ways in which we may represent an algorithm;
  • We use many techniques to represent an algorithm in computer
  • programming. The techniques that will study are:
    • Flowchart
    • Pseudocde

Prepared by Department of Preparatory year

slide19

Why Flowcharts:

  • The flowchart is graphical representation of the steps
  • required for an algorithm or program.
  • The flowchart is characterized by:
      • Clarify the program logic
      • Identify alternative processing methods
      • Serve as guide for program coding
      • Serve as documentation

Prepared by Department of Preparatory year

slide20

Principals of Flowchart

  • 1. Simplicity:
      • Easy to put on paper
      • Easy to draw
      • Readable and meaningful
  • 2. Organization:
  • - putting ideas together and organizing those ideas in logical way.
  • 3. Planning:
  • - flowchart helps for looking the program in deeper and global way.

Prepared by Department of Preparatory year

slide21

General Concepts

  • Flowchart must be characterized by the following:
    • The major element of the project.
    • Elements are clearly labeled.
    • Sequence of element must be clear.
    • No gap or dead ends.
    • Sequence of elements must be in logical form.
    • Flowchart must be used correctly.

Prepared by Department of Preparatory year

slide22

Levels of Program Flowchart

  • Simple sequential flowchart.
  • Branched flowchart.
  • Simple-loop flowchart.
  • Multi-loop flowchart.

Prepared by Department of Preparatory year

slide24

Example:1 Algorithm for reading student name

  • Start
  • Read student name
  • End

start

Read student name

Stop

Prepared by Department of Preparatory year

slide25

Example:2 Algorithm for calculate the area of circle

start

  • Start
  • Read value of R
  • Set PI equal to 3.14
  • Calculate Area=PI*R*R
  • Print R, Area
  • Stop

Read R

PI=3.14

Area=Pi*R*R

Print R, Area

Stop

Prepared by Department of Preparatory year

slide26

Example:3 Draw flow chart for evaluating the following

functions: F(X)=x if X>=0, F(X)= -X if X<0

start

  • Start
  • Read X
  • If X>=0 then go to step 4, else step 5
  • Calculate F(X)=X than go to step 6
  • Calculate F(X)=X
  • Print X, F(X)
  • Stop

Read X

X>=0

Yes

No

F(x)=x

F(x)= -x

A

Print x, F(x)

Stop

Prepared by Department of Preparatory year

slide27

Start

Read a, b

c = a+ b

Print c

Stop

Example:4 Write an algorithm and draw the flow chart to add two

numbers.

  • Algorithm:
  • Start
  • Read a, b
  • Calculate c=a + b
  • Print c
  • Stop

Flow chart:

Prepared by Department of Preparatory year

slide28

Start

Read r

c =2 * 3.14 * r

Print c

Stop

Exercise 5:Write an algorithm and draw the flow chart to find the circumference of circle

  • Algorithm:
  • Start
  • Read r
  • Calculate c= 2*3.14 * r
  • Print c
  • Stop

Prepared by Department of Preparatory year

slide29

Flowchart Levels

First Level of Flowchart

It is simplest level which contain the sequence of steps without loops or branch and the flowchart comes in straight line from the beginning to the end.

Prepared by Department of Preparatory year

slide30

Second Level of Flowchart

It is branched flowchart, when there is a condition statement in the program.

Look at the following example:

Prepared by Department of Preparatory year

slide31

Third Level of Flowchart

  • It is a flowchart which contain iteration or repetitions. It is
  • usually called loop flowcharts.
  • In this type we need to repeat some operation several times
  • using the same set of operation.
  • The general from for this type is as follows:

condition

No

Yes

operation

Prepared by Department of Preparatory year

slide32

Exercise 6:write an algorithm and draw a flowchart for printing 10 integers starting from 1

start

  • Algorithm:
  • Start
  • Take the initial value of A=1
  • Check if A>=10 if yes and
  • If no print the number and increment A by 1

A=1

A>=10?

Yes

No

End

A=A+1

Print A

Prepared by Department of Preparatory year

looping
Looping
  • When we need to use a loop a special symbol can be used

Loop

i = 0,N,M

Counter i

Any Initial value

Final Value (N)

Increment or Decrement Value (M)

Instructions to be executed

M

Prepared by Department of Preparatory year

homework
Homework
  • Write an algorithm and draw a flowchart to calculate and print the sum of numbers from 1 to 100 .

Prepared by Department of Preparatory year