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A structure type can contain a number of dissimilar data objects within it. Unlike a simple variable (which contains only one data object) or an array (which, although it contains more than one data item, only contains items of a single data type),a structure is a collection of related data of different types. a name, for example, might be array of characters, an age might be integer. A structure representing a person, say, could contain both a name and an age, each represented in the appropriate format.

Declarations and usage of structures

Until now, all the data that we have dealt with has been either of a basic type such as char, int and double…, or an array of those types. However, there are many situations in real life where a data item needs to be made up from other more basic types. We could do this with an array if the constituent types were all the same, but often they are different. For example, suppose we want to record the details of each student in a class. The detail of each student might be as follow:

  • A unique student number, which could be represented as a string (an array of char ).
  • The student’s name, which could be represented as a string (an array of char ).
  • Final mark for the Introduction to computer science course, which is a floating point value (a float ).

Creating structures as new data types

The definition of a structure type begins with the keyword struct, and contains a list of declarations of the structure's members, in braces:

struct structTag {<list of members>; };
Definition ends with semicolon (;)

The three components above can be placed in a structure declared like this:

struct Student {char StudentID[10];char name[30];float markCS ; };
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The keyword struct introduces a structure declaration, which is a list of declarations enclosed in braces. An optional name called a structure tag may follow the word struct (as with Student here). The tag names this kind of structure, and can be used subsequently as a shorthand for the part of the declaration in braces. The variables named in a structure are called members. A structure member or tag and an ordinary (i.e., non-member) variable can have the same name without conflict, since they can always be distinguished by context. Furthermore, the same member names may occur in different structures, although as a matter of style one would normally use the same names only for closely related objects.

Creating variable of a struct type

Structure types are not considered a variable declaration, just definition of a new type, so they cannot store anything until we declare variable of this type. Here is how we would create:

type_name_of_struct name_of_variable;

Creating three variables a, b, c of the Student type:

Student a, b, c;

Creating an array of the Student type:

Student studentCS[50];
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A member of a structure may have any desired complete type, including previously defined structure types. They must not be variable-length arrays, or pointers to such arrays. For instance, now we want to record more information of students, for example their date of birth, which comprises the day, month and year. So first, let's start with the date, because that is a new type that we may be able to use in a variety of situations. We can declare a new type for a Date thus:

Questions & Answers

how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
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 ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
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.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
what is biological synthesis of nanoparticles
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
many many of nanotubes
what is the k.e before it land
what is the function of carbon nanotubes?
I'm interested in nanotube
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
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
what is system testing
what is the application of nanotechnology?
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
anybody can imagine what will be happen after 100 years from now in nano tech world
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
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
silver nanoparticles could handle the job?
not now but maybe in future only AgNP maybe any other nanomaterials
I'm interested in Nanotube
this technology will not going on for the long time , so I'm thinking about femtotechnology 10^-15
can nanotechnology change the direction of the face of the world
Prasenjit 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, Introduction to computer science. OpenStax CNX. Jul 29, 2009 Download for free at http://cnx.org/content/col10776/1.1
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