# 2.4 Repetition statements, arrays and structured programming  (Page 6/8)

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`set the average to the total divided by the counter`

`print the average`

`else`

`Print “No grades were entered”.`

Final step: After coding, we come to the following C++ program.

`#include<iostream.h>`

`#include<iomanip.h>`

`int main()`

`{`

`int total, // sum of grades`

`gradeCounter, // number of grades entered`

`grade; // one grade`

`double average; // number with decimal point for average`

`// initialization phase`

`total = 0;`

`gradeCounter = 0;`

`// processing phase`

`cout<<"Enter grade, -1 to end: ";`

`cin>>grade;`

`while ( grade != -1 ) {`

`total = total + grade;`

`gradeCounter = gradeCounter + 1;`

`cout<<"Enter grade, -1 to end: ";`

`cin>>grade;`

`}`

`// termination phase`

`if ( gradeCounter != 0 ) {`

`average = double ( total ) / gradeCounter;`

`cout<<"Class average is "<<setprecision( 2 )`

`<<setiosflags( ios::fixed | ios::showpoint )`

`<<average<<endl;`

`}`

`else`

`cout<<"No grades were entered"<<endl;`

`return 0;`

`}`

## Arrays

An array is an advanced data type that contains a set of data represented by a single variable name.

An element is an individual piece of data contained in an array.

## Array declaration

The syntax for declaring an array is

`type name[elements];`

Array names follow the same naming conventions as variable names and other identifiers.

Example:

`int MyArray[4];`

`char StudentGrade[5];`

The declaration int MyArray[3]; tells the compiler to reserve 4 elements for integer array MyArray.

The numbering of elements within an array starts with an index number of 0. An index number is an element’s numeric position within an array. It is also called a subsript.

Each individual element is referred to as an indexed variable or a subscripted variable because both a variable name and an index or subscrip value must be used to reference the element.

Example:

Subscripted variables can be used anywhere scalar variables are valid. Examples using the elements of the MyArray array are:

`MyArray[0] = 17;`

`MyArray[1] = MyArray[0]– 11;`

`MyArray[2] = 5*MyArray[0];`

`MyArray[3] = (MyArray[1]+ MyArray[2] –3)/2;`

`Sum = MyArray[0] +MyArray[1]+MyArray[2] + MyArray[3];`

## Example

`#include<iostream.h>`

`int main(){`

`char StudentGrade[5]= {‘A’, ‘B’, ‘C’, ‘D’, ‘F’};`

`for ( int i = 0; i<5; i++)`

`cout<<StudentGrade[i]<<endl;`

`return 0;`

`}`

The output is:

A

B

C

D

F

## Example

`// Compute the sum of the elements of the array`

`#include<iostream.h>`

`int main()`

`{`

`const int arraySize = 12;`

`int a[ arraySize ] = { 1, 3, 5, 4, 7, 2, 99, 16, 45, 67, 89, 45 };`

`int total = 0;`

`for ( int i = 0; i<arraySize; i++ )`

`total += a[ i ];`

`cout<<"Total of array element values is "<<total<<endl;`

`return 0 ;`

`}`

The output of the above program is as follows :

Total of array element values is 383

## Multi-dimensional arrays

The C++ language allows arrays of any type, including arrays of arrays. With two bracket pairs we obtain a two-dimensional array. The idea can be iterated to obtain arrays of higher dimension. With each bracket pair we add another array dimension.

where we get a research paper on Nano chemistry....?
what are the products of Nano chemistry?
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
learn
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
learn
da
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Bhagvanji
Preparation and Applications of Nanomaterial for Drug Delivery
revolt
da
Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
I only see partial conversation and what's the question here!
what about nanotechnology for water purification
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
Damian
yes that's correct
Professor
I think
Professor
Nasa has use it in the 60's, copper as water purification in the moon travel.
Alexandre
nanocopper obvius
Alexandre
what is the stm
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
Rafiq
if virus is killing to make ARTIFICIAL DNA OF GRAPHENE FOR KILLED THE VIRUS .THIS IS OUR ASSUMPTION
Anam
analytical skills graphene is prepared to kill any type viruses .
Anam
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
Hafiz
what is Nano technology ?
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
why we need to study biomolecules, molecular biology in nanotechnology?
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
why?
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
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