Which loop in C does NOT check the condition before executing the loop body?

The correct answer is C: do-while loop. The do-while loop executes the loop body at least once before checking the condition. Other loops check the condition before execution. Syntax: do { } while(condition);

What is the difference between struct and union in C?

The correct answer is B: union members share memory, struct members have separate memory. In a struct, each member has its own memory allocation, so the total size is the sum of all members. In a union, all members share the same memory location, so the size equals the largest member. Only one member can hold a value at a time in a union.

What is the time complexity of quicksort algorithm in the worst case?

The correct answer is B: O(n²). Quicksort's worst-case complexity is O(n²) when pivot selection is poor, though average case is O(n log n).

Which data structure uses the LIFO (Last In First Out) principle and is commonly used for function call management in programming languages?

The correct answer is B: Stack. A Stack follows LIFO principle where the last element inserted is the first one to be removed. It is fundamental in managing function calls through the call stack, undo/redo operations, and expression evaluation. Queues use FIFO, Heaps are used for priority ordering, and Linked Lists maintain sequen

Consider a structure with bit fields. What will be the size of the following structure in bytes? struct demo { unsigned int a : 5; unsigned int b : 3; unsigned int c : 4; unsigned int d : 7; };

The correct answer is C: 4 bytes. Bit fields in C are packed into the smallest integral type that can accommodate them. Here, a(5) + b(3) + c(4) + d(7) = 19 bits total. Since 19 bits exceed 16 bits but fit within 32 bits, the compiler allocates 4 bytes (32 bits) for this structure, following standard packing rules.

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Q.81 Medium C Programming

What is the correct way to declare a function that takes no parameters and returns an integer?

A int func();

B int func(void);

C func() returns int;

D int func(no parameters);

Correct Answer: B. int func(void);

EXPLANATION

To explicitly declare a function with no parameters in C, use 'void' as the parameter. int func(); is ambiguous in older C standards.

Test

Q.82 Medium C Programming

In C, what is the purpose of the #define directive?

A To define functions

B To define macros or constants

C To declare variables

D To include header files

Correct Answer: B. To define macros or constants

EXPLANATION

#define is a preprocessor directive used to define symbolic constants (macros) and performs text substitution before compilation.

Test

Q.83 Medium C Programming

Which of the following is used to access members of a structure using a pointer?

A Dot operator (.)

B Arrow operator (->)

C Ampersand (&)

D Asterisk (*)

Correct Answer: B. Arrow operator (->)

EXPLANATION

The arrow operator (->) is used to access structure members through a pointer. The dot operator (.) is used for direct access.

Test

Q.84 Medium C Programming

What does the break statement do in a loop?

A Skips the current iteration

B Terminates the loop immediately

C Pauses the loop

D Restarts the loop

Correct Answer: B. Terminates the loop immediately

EXPLANATION

The break statement immediately terminates the loop and transfers control to the statement following the loop.

Test

Q.85 Medium C Programming

What is the default return type of a function in C if not explicitly specified?

A void

B int

C char

D float

Correct Answer: B. int

EXPLANATION

In C, if a function's return type is not explicitly specified, it defaults to int. However, modern C standards require explicit return type declaration.

Test

Q.86 Medium C Programming

Which of the following correctly initializes an array of 5 integers?

A int arr[5] = {1, 2, 3, 4, 5};

B int arr(5) = {1, 2, 3, 4, 5};

C int [5] arr = {1, 2, 3, 4, 5};

D int arr[5];

Correct Answer: A. int arr[5] = {1, 2, 3, 4, 5};

EXPLANATION

Arrays in C are declared with square brackets containing the size, followed by initialization in curly braces. Option A is the correct syntax.

Test

Q.87 Medium C Programming

What is the purpose of the malloc() function in C?

A To deallocate memory

B To allocate memory dynamically at runtime

C To initialize variables

D To declare arrays

Correct Answer: B. To allocate memory dynamically at runtime

EXPLANATION

malloc() (memory allocation) allocates a block of memory dynamically during program execution and returns a pointer to it.

Test

Q.88 Medium C Programming

In C, a pointer variable stores which of the following?

A The actual value of a variable

B The memory address of a variable

C The size of a variable

D The data type of a variable

Correct Answer: B. The memory address of a variable

EXPLANATION

A pointer is a variable that stores the memory address of another variable. It is declared using the * symbol.

Test

Q.89 Medium C Programming

What will be the output of the following C code?
int x = 10;
int y = 20;
int z = x < y ? x++ : y++;
printf("%d %d %d", x, y, z);

A 10 20 10

B 11 20 10

C 10 21 20

D 11 21 10

Correct Answer: B. 11 20 10

EXPLANATION

Step 1: Evaluate condition x < y → 10 < 20 → true. Step 2: Execute true branch: x++ returns 10, then x becomes 11. Step 3: z = 10. Step 4: printf prints x=11, y=20, z=10.

Test

Q.90 Medium C Programming

Which of the following correctly describes the scope of a static variable declared inside a function?

A Local to the function, retains value between function calls

B Global scope, initialized once

C Local to the file only

D Creates a new instance on each function call

Correct Answer: A. Local to the function, retains value between function calls

EXPLANATION

A static variable declared inside a function has local scope (visible only within that function) but persists for the entire program lifetime. Its value is retained between function calls and is initialized only once.

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