Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.

Structures bmn

157 views

Published on

Definition, Declaration of Structures

Published in: Education
  • Be the first to comment

Structures bmn

  1. 1. Structures Definition: A structure is a collection of similar or different elements (data types) grouped together Structure Declaration: The general form of a structure declaration statement is given below: struct structure name { structure element 1 ; structure element 2 ; structure element 3 ; ...... ...... };
  2. 2. Structure variables: Once the structure is defined, structure variables can be declared as: struct structure_name variable 1, variable 2,……., variable n; E.g.: struct book { char name ; float price ; int pages ; }; struct book b1, b2, b3 ;
  3. 3. Rules of structure declaration • The closing brace in the structure type declaration must be followed by a semicolon. • It is important to understand that a structure type declaration does not tell the compiler to reserve any space in memory. All a structure declaration does is, it defines the ‘form’ of the structure. • Usually structure type declaration appears at the top of the source code file, before any variables or functions are defined.
  4. 4. Initialization of structure at the time of declaration Structure variables can also be initialized where they are declared. The format used is as follows: Eg. struct book { char name[10] ; float price ; int pages ; } ; struct book b1 = { "Maths", 130.00, 550 } ; struct book b2 = { "Physics", 150.80, 800 } ;
  5. 5. Accessing elements of structure Structures use a dot (.) operator to access individual elements. Eg: struct book { char name ; float price ; int pages ; } ; struct book b1, b2, b3 ; So to refer to pages of the structure defined we have to use, b1.pages Similarly, to refer to price we would use, b1.price Before the dot there must always be a structure variable and after the dot there must always be a structure element.
  6. 6. Storing Structure Elements Whatever be the elements of a structure, they are always stored in contiguous memory locations. Eg: struct book { char name; float price ; int pages ; } ; struct book b1 = { "C", 130.00, 550 } ; For the above structure, the elements are stored in memory as shown: Elements b1.name b1.price b1.pages Address 5001 5002 5006 C 130.00 550 C 130.00 550

×