Structures and Unions

Question 1

What is a struct in C?

Answer 1

A user-defined data type that allows grouping variables of different data types under a single name, useful for representing records.

Question 2

How do you access members of a structure variable using the dot operator (.)?

Answer 2

structureVariable.memberName

Question 3

When accessing a structure member through a pointer to the structure, which operator do you use?

Answer 3

The arrow operator (->). E.g., structurePointer->memberName.

Question 4

What is a union in C? How does it differ from a struct in terms of memory usage?

Answer 4

A user-defined data type where all its members share the same memory location. The size of a union is equal to the size of its largest member, unlike a struct which sums the sizes of its members. Only one member can hold a value at any given time.

Question 5

When would you choose a union over a struct?

Answer 5

When you need to store only one of several possible data types at a time, to save memory.