Consider: union Data { int i; float f; char c; }; What is the size of this union?
Answer: A
The size of a union equals the size of its largest member. Here, int is 4 bytes (largest), so union size is 4 bytes.
Q.22Easy
How do you access a member of a structure through a pointer in C?
Answer: B
The arrow operator (->) is used to access structure members through a pointer. The dot operator is used with direct variables.
Q.23Easy
Which of the following correctly demonstrates a typedef for a structure?
Answer: A
The correct syntax for typedef struct is: typedef struct { members } StructName;
Q.24Easy
Which of the following is the correct way to initialize a structure in C?
Answer: A
Structures must be initialized at declaration time using curly braces. Assignment of initializer list is not valid after declaration.
Q.25Easy
Which of the following statements about structures is TRUE?
Answer: B
A structure allows grouping of different data types. Padding may be added by the compiler for alignment.
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Q.26Easy
Consider the following code:
struct Data {
int a;
char b;
};
struct Data d = {10, 'A'};
Which method of initialization is used here?
Answer: B
Values are assigned in the order they appear in the structure definition, which is positional initialization.
Q.27Easy
What is the primary difference between a struct and a union in C?
Answer: A
In a union, all members occupy the same memory space, while struct members have individual memory locations.
Q.28Easy
Which of the following correctly demonstrates accessing a member of a pointer to a structure?
Answer: B
Both (*ptr).member and ptr->member are valid. Option B uses explicit dereferencing, while the arrow operator is syntactic sugar for this.
Q.29Easy
In C, what does the 'typedef' keyword do when used with structures?
Answer: A
typedef creates an alias, allowing you to use the structure name directly without using 'struct' keyword.
Q.30Easy
Given: struct Node { int data; struct Node *next; }; This represents which data structure concept?
Answer: B
A self-referential structure with a single pointer member is the fundamental building block of a singly linked list.
Q.31Easy
In the context of structures, what does 'self-referential' mean?
Answer: A
Self-referential structures contain pointers to their own type, enabling dynamic data structures like linked lists and trees.
Q.32Easy
What is the key difference between a structure and a union in C?
Answer: B
In structures, memory is allocated for each member independently. In unions, all members share the same memory location, so total memory allocated equals the size of the largest member.
Q.33Easy
struct Node { int data; struct Node *next; }; This is an example of which design pattern?
Answer: B
A self-referential structure contains a pointer to its own type. This is the fundamental building block for creating linked lists, trees, and other dynamic data structures.
Q.34Easy
Given a structure with array members, how would you efficiently pass it to a function to avoid copying overhead?
Answer: B
Passing a pointer to the structure avoids copying the entire structure in memory, which is especially important for large structures with array members. This improves performance significantly.
