In this PPTX i show you basic concept of function,struct,pointer etc.These are fundamentals of data structure.

1. Data Structure 1
Pointer,
Function, structure, array,
recursive function call

2. Pointers

3. Introduction
• Pointers
– Pointers are variables containing memory addresses of a
variable with specific value.
– A variable name directly references a value
– A pointer indirectly reference a value.
– A pointer ‘p’ pointing to a character ‘c’ –

4. Pointer Variable Declarations and
Initialization
• Pointer variables
– Contain memory address as their value
– Normal variables contain a specific value (direct reference)
– Pointers contain address of a variable that has a specific
value (indirect reference)
– Indirection – referencing a pointer value
• Pointer declarations
– * used with pointer variables: e.g., int *myPtr;
– Declares a pointer to an int (pointer of type int *)
– Multiple pointers require using a * before each variable declaration:
int *myPtr1, *myPtr2;

5. – Can declare pointers to any data type
– Initialize pointers to 0, NULL, or an address
• 0 or NULL –points to nothing (NULL preferred)

6. Calling Functions by Reference
• Call by reference with pointer arguments
– Pass address of argument using & operator
– Allows you to change actual location in memory
– Arrays are not passed with & because the array
name is already a pointer.

7. Pointer Expressions and Pointer
Arithmetic
• Arithmetic operations can be performed on
Pointers
– Increment/decrement pointer (++ or --)
– Add an integer to a pointer( + or += , - or -=)
– Pointers may be subtracted from each other

8. • 5 element int array on machine with 4 byte int
– vPtr points to first element v[ 0 ]
– at location 3000 (vPtr = 3000)
– vPtr += 2; sets vPtr to 3008
– vPtr points to v[ 2 ] (incremented by 2),
but the machine has 4 byte int, so it points to address 3008

9. sizeof Operator
• Sizeof
– Returns size of operand in bytes
– For arrays: size of 1 element *number of elements
– sizeof can be used with
• Variable names
• Type name
• Constant values

10. Relationship Between Pointers and
Arrays
• Arrays and pointers closely related
– Array name like a constant pointer
– Pointers can do array subscripting operations

11. Pointer-to-pointers
• We can have pointers to – int, char, float, any
structure….
• Declaration of a pointer-to-pointer:
• int
**ipp; where two * indicates two level of
pointers.

12. • ipp points to ip1 which points to i.
• **ipp is i, or 10.

13. Pointers to Functions
• Pointer to function
– Contains address of function
– Similar to how array name is address of first element
– Function name is starting address of code that defines
Function
• Function pointers can be
– Passed to functions
– Stored in arrays
– Assigned to other function pointers

14. Data Structure Books
• Text Books:
• Mark Allen Weiss - Data Structures and Algorithm Analysis in
C, 2nd Edition, Addison-Wesley, 1997
• P.S. Deshpande and O.G. Kakde - C and Data Structures,
Charles Rive Media, 2004
• Reference Books:
• Data structures and problem solving using C++, By Mark Allen
Weiss - Addison-Wesley (2000)