Question

What are differences between structure and union by coding example in C language?

Answer 1

1)

The struct keyword is used to define a structure
The union keyword is used to define a union

2)

When a variable is associated with a structure, the compiler allocates
the memory for each member. The size of structure is greater than or equal to the sum of size of its members.

When a variable is associated with a union the compiler allocates the memoryby cinsidering the size of
the largest memory. So, size of the union is equal to the size of largest member.

3)
In structure each member within a strucure is assigned unique storeage area of location.
Where in union memory allocated is shared by individual memebers of union.

4)

In structure altering value of a member will not affect other members of the structure.
In union altering value of any of the member will alter other memebers value;

5)

In structure individual memeber van be accessed at a time
In union only on member can be accessed at time

6)

Several members of a structure can intialize at once.
Only the first member of a union can be initialized.

// declaring structure
struct person
{
int id;
float salary;
char name[20];
};

// declaraing union

union employee
{
int empId
float rate;
char name[20];
};

If you have any query regarding the answer please ask me in the comment i am here for help you. Please do not direct thumbs down just ask if you have any query. And if you like my work then please appreciates with up vote. Thank You.