# 1.3 Scr0330: sequence, selection, and loop in scratch 2.0.  (Page 2/9)

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## Images

• Image 1 . The sequence structure in pseudocode.
• Image 2 . The selection structure in pseudocode.
• Image 3 . The loop structure in pseudocode.
• Image 4 . Scratch 2.0 programming interface for the program named IfSimple01.
• Image 5 . A paraphrased version of the Scratch code.
• Image 6 . Program code for the left beachball
• Image 7 . Initializing the position and orientation of the basketball.
• Image 8 . All of the code that applies to the basketball.
• Image 9 . Pseudocode for a selection structure.
• Image 10 . Two independent decisions.
• Image 11 . Control structures available in Scratch.
• Image 12 . Programming blocks belonging to the Sensing group.
• Image 13 . Initial output from the program named IfWithVar01.
• Image 14 . Program output after having clicked twice in the Stage area.

## General background information

• Structured programming.
• The sequence structure.
• The selection structure.
• The loop structure.

In introductory programming courses, you will often hear a lot about something called structured programming. In comparison with more modern and complex programming concepts such as runtime polymorphism, structured programming is fairly mundane. However, that's not to say that structured programming isn'timportant. It is very important. But it is just a small bump in the road of learning that leads to a more complete understanding of computerprogramming, especially object-oriented programming.

## What is structured programming ?

Basically, the concept of structured programming says that any programming logic problem can be solved using an appropriate combination of only threeprogramming structures, none of which are complicated. The three structures are known generally as:

• The sequence structure.
• The selection or decision structure .
• The loop, repetition, or iteration structure.

## One door in and one door out

To understand structured programming, you need to think in terms of a section of program code that has only one entry point and one exit point. It isvery important that there cannot be multiple entry points or multiple exit points.

There must be only one way into the section of code and one way out of the section of code.

## Nesting of structures is allowed

Another important part of the concept is that structures may be nested inside of other structures provided that every structure meets the basic rules for astructure.

Thus, by nesting simple structures inside of simple structures, large and complex overall structures can be constructed.

## Pseudocode

Computer programming source code consists generally (but not in Scratch) of programming instructions written in text form with a very specific format or syntax that is designed to be understood by a computerprogram. (This is commonly called source code.) Humans who are not computer programmers might not be expected to understand much of what they see in computer programming source code.

According to Wikipedia ,

"The prefix pseudo - (from Greek... "lying, false") is used to mark something as false, fraudulent, or pretending to be something it is not."

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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