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Exercise Write equivalent programs using a while loop and a do-while loop.

Counting with for statements

Concept Although all loop structures can be programmed as while loops, one special case is directly supported: writing a loop that executes a predetermined numberof times. The for statement has three parts:

for (int i = 0; i<N; i++)

The first part declares a loop control variable and gives it an initial value. The second part contains the exit condition: the loop body will be executedas long as the expression evaluates to true. The third part describes how the value of the control variable is modified after executing the loop body.The syntax show is the conventional one for executing a loop N times.

Program: Control06.java

// Learning Object Control06 //    counting with for statementspublic class Control06 {     static final int N = 6;    public static void main(/*String[] args*/) {        int factorial = 1;         for (int i = 0; i < N; i++)             factorial = factorial * (i+1);        System.out.println(factorial);     }}

This program computes the first six factorials in a for loop and the last value is printed.

  • The constant N and the variable factorial are allocated and initialized.
  • The control variable i is allocated and initialized.
  • The expression i<N is evaluated and evaluates to true.Jeliot displays Entering the for loop .
  • The loop body is executed.
  • The control variable is incremented as specified in the third part of the for statement.
  • The previous three steps are repeated until the expression evaluates to false; this causes the loop to be exited. Jeliot displays Continuing the for loop as long as the expression evaluates to true, and Exiting the for loop when it evaluates to false.
  • The final value of factorial is printed.
  • Important : when the loop is exited, the control variable is deallocated and no longer exists.

Exercise Rewrite the program using a while loop.

General for statements

Concept Arbitrary expressions can be given for the initial value of the for statement, the exit condition, and the modification of the control variable.

Program: Control07.java

// Learning Object Control07 //    General for statementspublic class Control07 {     static final int N = 100;    public static void main(/*String[] args*/) {        int sum = 0;         for (int i = 0; i < Math.sqrt(N); i = i + 3)             sum = sum + i;        System.out.println(sum);     }}

This program computes the sum of multiples of three that are less than the square root of N .

  • The constant N and the variable sum are allocated and initialized.
  • The control variable i is allocated and initialized.
  • The expression i<Math.sqrt(N) is evaluated and evaluates to true. Jeliot displays Entering the for loop .
  • The loop body is executed.
  • The control variable is incremented by three as specified in the third part of the for statement.
  • The previous three steps are repeated until the expression evaluates to false; this causes the loop to be exited. Jeliot displays Continuing the for loop as long as the expression evaluates to true, and Exiting the for loop when it evaluates to false.
  • The final value of sum is printed.
  • Important : when the loop is exited, the control variable is deallocated and no longer exists.

Questions & Answers

Do somebody tell me a best nano engineering book for beginners?
s. Reply
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
s.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Harper
how to fabricate graphene ink ?
SUYASH Reply
for screen printed electrodes ?
SUYASH
What is lattice structure?
s. Reply
of graphene you mean?
Ebrahim
or in general
Ebrahim
in general
s.
Graphene has a hexagonal structure
tahir
On having this app for quite a bit time, Haven't realised there's a chat room in it.
Cied
what is biological synthesis of nanoparticles
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
China
Cied
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
Porter
many many of nanotubes
Porter
what is the k.e before it land
Yasmin
what is the function of carbon nanotubes?
Cesar
I'm interested in nanotube
Uday
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
AMJAD
preparation of nanomaterial
Victor Reply
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
Himanshu Reply
good afternoon madam
AMJAD
what is system testing
AMJAD
what is the application of nanotechnology?
Stotaw
In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
Azam
anybody can imagine what will be happen after 100 years from now in nano tech world
Prasenjit
after 100 year this will be not nanotechnology maybe this technology name will be change . maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
Azam
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
Prasenjit
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
Damian
silver nanoparticles could handle the job?
Damian
not now but maybe in future only AgNP maybe any other nanomaterials
Azam
Hello
Uday
I'm interested in Nanotube
Uday
this technology will not going on for the long time , so I'm thinking about femtotechnology 10^-15
Prasenjit
can nanotechnology change the direction of the face of the world
Prasenjit Reply
At high concentrations (>0.01 M), the relation between absorptivity coefficient and absorbance is no longer linear. This is due to the electrostatic interactions between the quantum dots in close proximity. If the concentration of the solution is high, another effect that is seen is the scattering of light from the large number of quantum dots. This assumption only works at low concentrations of the analyte. Presence of stray light.
Ali Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Learning objects for java (with jeliot). OpenStax CNX. Dec 28, 2009 Download for free at http://cnx.org/content/col10915/1.2
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