Lec-4

Question 1

What are the sizes of common data types in C?

Answer 1

char: 1 byte
int: 4 bytes
float: 4 bytes
double: 8 bytes
long: 8 bytes

Question 2

What are the rules for identifiers in C?

Answer 2

Identifiers consist of A-Z, a-z, 0-9, and underscore, are case-sensitive, cannot start with a number, and cannot be a keyword.

Question 3

What are best practices for naming identifiers?

Answer 3

Use meaningful names, limit to 31 characters, use lowercase for single syllables, and use underscore or camel case for multiple syllables.

Question 4

What does the scanf() function do?

Answer 4

Reads input from standard input, uses format specifiers, and requires the address operator (&).

Question 5

What does the printf() function do?

Answer 5

Outputs formatted text, uses conversion specifiers, and allows direct calculations within output.

Question 6

What are some common format specifiers in C?

Answer 6

%c: Characters
%f: Floats
%lf: Doubles
%d: Integers
%s: Strings

Question 7

How are constant variables declared in C?

Answer 7

Declared with ‘const’ keyword, must be initialized during declaration, and cannot be modified after initialization.

Question 8

What is the purpose of the #define preprocessor directive?

Answer 8

Creates symbolic constants, replaces identifiers before compilation, and provides global constant definitions.

Question 9

What are the advantages of using constants in C programming?

Answer 9

Improve code readability, eliminate ‘magic numbers’, and facilitate easier program maintenance.