The document discusses the use of pointers in C programming, specifically relating to arrays and structures. It explains how to create pointers to arrays and structures, access their elements, and perform operations such as reading and writing data. Additionally, it covers the concept of pointers to arrays of structures, illustrating usage through examples.

1. Pointer to Array and
Structure
Prepared By: Mr. S. A. Patil
Assistant Professor,PVPIT Budhgaon

2. Pointers to Array
 Array is collection elements with same datatype.
 When we create an array some memory space is allocated to that array.
 So we can create pointer of array also.
 By using pointer to array we can access elements of array

3. Example
int numbers[5]={10,20,30,40,50};
int *p;
p=&numbers; // p=numbers;
this store address of first element of the array. And once we store address of first
element of array we can access by using *(p+1),*(p+2) and so on.

4. Access array using pointer
int numbers[5]={10,20,30,40,50};
int *p,i;
p=&numbers; // p=numbers;
for( i=0; i<5 ; i++)
{
printf(“n%d”,*(p+i));
}

5. Pointer to structure
 Structure is collection of elements with different datatypes.
 When we define any structure we create a user defined datatype of structure type.
 Memory is allocated to each structure variable.
 We can also create pointer to structure variable.
 And access structure by using pointer

6. Example
struct student
{
int roll;
float marks;
};
struct student s1;
struct student *ptr;
ptr=&s1;

7. Access structure elements using pointer
 We can access structure elements by using -> operator
 Write data into structure variable
printf(“nEnter Roll No:”);
scanf(“%d”,&ptr->roll);
printf(“nEnter Marks:”);
scanf(“%f”,&ptr->marks);
 Read structure variable
printf(“nRoll number: %d”,ptr->roll);
printf(“nMarks: %f”,ptr->marks);

8. Pointer to array of structure
 It is possible to create pointer to array of structure as regular array.
struct student
{
int roll;
float marks;
};
struct student s[5];
struct student *ptr;
ptr=&s;

9. Access array of structure using pointer
 We can access structure elements by using -> operator
 Write data into structure variable
for(i=0;i<5;i++)
{
printf(“nEnter Roll No:”);
scanf(“%d”,&ptr->roll);
printf(“nEnter Marks:”);
scanf(“%f”,&ptr->marks);
ptr++;
}

10. Access array of structure using pointer
 Read structure variable
for(i=0;i<5;i++)
{
printf(“nRoll number: %d”,ptr->roll);
printf(“nMarks: %f”,ptr->marks);
ptr++;
}