lesson 1 introduction to programming language. computer comprised of various devices that are...

LESSON 1

Introduction to Programming Language

ComputerComprised of various devices that are referred to as HARDWARE.

The computer programs that run of a computer are referred to SOFTWARE.

Computer ProgramSet of instructions used to operate a computer to perform specific task and produce result

Computer ProgrammingWriting computer program

Programming LanguageLanguage used to create computer programs

Levels of Programming Languages

Machine LanguagesAssembly LanguagesHigh Languages

Machine Language

Lowest level of computer languages

Only language that computer can understand.

Consist entirely of 1s and 0s. Easily understood by computers

but difficult to read by people.

Assembly LanguageUses symbolic names and operands instead of 1s and Os e.g. MOV and ADD

Needs ASSEMBLER to translate instruction to machine level language

High-Level Languages English like language instructions

so it is easier to learn, use and debug the program.

Example FORTRAN, COBOL, BASIC, PASCAL, C,

C++ and JAVA It needs the help of COMPILER to

be understood by the computer

What is Compiler Translates the high level

program(source code) into machine code(object code).

High Level Program Compiler Machine Code0,1

History of C++ In 1970s, at Bell Laboratories, Dennis

Ritchie and Brian Kernighan designed the C programming language.

Most of C is a subset of C++ C++ was developed by Dr. Bjarne

Stroustrup in 1985 at AT&T Bell Labs New Jersey, USA.

Initially called as “C with classes” but was change to C++

An ALGORITHM is a detailed sequence of simple steps that are needed to solve a problem.

An algorithm is defined as a step-by-step sequence of instructions that describes how the data are to be processed to produce the desired outputs.

Algorithm

1. Start 2. Accept num1, num2 3. sum = num1+num2 4. Display sum 5. Stop

Write an algorithm to find sum of two numbers.

Sample 1

1. Start 2. Accept q1, q2, q3 3. total = q1 + q2 + q3 4. average = total / 3 5. Display total, average 6. Stop

Write an algorithm find the total and average of three quizzes.

Sample 2

Write an algorithm to determine a student’s final grade and indicate whether it is passing or failing. The final grade is calculated as the average of four marks.

Sample 3

Sample 3

Step 1: StartStep 2: Input M1, M2, M3, M4 Step 3: GRADE = (M1+M2+M3+M4)/4 Step 4: if (GRADE < 50) then Print “FAIL”

else Print “PASS” Step 5: Stop

A flowchart is a design tool used to graphically represent the logic in a solution. It is a pictorial representation or graphical representation of the algorithm.

Flowchart

Flowchart

Flowchart

Write a flowchart to find sum of two numbers

Sample 1

1. Start 2. Accept num1, num2 3. sum = num1+num2 4. Display sum 5. Stop

Exercises Question 1. Write an algorithm and draw

the flowchart to read money in US dollar and convert to Omani rials. rials = dollar * 2.50

Answer1. Start2. Accept dollar3. Rials = dollar * 2.504. Display rials5. Stop

start

Accept dollar

rials = dollars * 2.50

Display rials

stop

Exercises Question 2. Write an algorithm and draw

the flowchart to calculate area of square and rectangle. Square Area = side * side Rectangle Area = length * width

Answer1. Start2. Accept side, length, width3. Square Area = side * side4. Rectangle Area = length *

width5. Display square and

rectangle area6. Stop

start

Accept side, length, width

Square area = side * sideRectangle area = length *

widthDisplay square and rectangle

areastop

Exercises Question 3. Write an algorithm and draw

the flowchart to determine if a number is positive or negative.

Answer1. Start2. Accept number3. If number<0 then

Print “negative” else

Print “positive”4. Stop

start

Accept side, length, width

Print “Positive”

stop

Print “Negative

”

If number

<0 NOYES

Exercises Question 2. Write an algorithm and draw

the flowchart to calculate area of square and rectangle. Square Area = side * side Rectangle Area = length * width

Answer1. Start2. Accept side, length, width3. Square Area = side * side4. Rectangle Area = length *

width5. Display square and

rectangle area6. Stop

start

Accept side, length, width

Square area = side * sideRectangle area = length *

widthDisplay square and rectangle

areastop

Exercises Question 2. Write an algorithm and draw

the flowchart to calculate area of square and rectangle. Square Area = side * side Rectangle Area = length * width

Answer1. Start2. Accept side, length, width3. Square Area = side * side4. Rectangle Area = length *

width5. Display square and

rectangle area6. Stop

start

Accept side, length, width

Square area = side * sideRectangle area = length *

widthDisplay square and rectangle

areastop