Mastering C Programming Concepts

What are the basic data types available in C?

• string

• array

• boolean

• int, float, double, char, void

Explain the difference between '==' and '===' in C.

• '==' is used for assignment, while '===' is for comparison

• '==' allows type coercion, while '===' does not.

• Both '==' and '===' are identical in functionality

• '==' is faster than '==='

What is a function in C and how is it defined?

• A function in C is a reusable block of code defined with a return type, name, and parameters.

• A function in C is defined only with a name and no return type.

• A function in C is a single line of code without parameters.

• A function in C is a type of variable that stores data.

Describe recursion and provide an example in C.

• int fibonacci(int n) { if (n <= 1) return n; return fibonacci(n + 1); }

• int sum(int n) { return n + sum(n - 1); }

• int factorial(int n) { if (n == 0) return 1; return n * factorial(n - 1); }

• int power(int base, int exp) { if (exp == 1) return base; return base * power(base, exp + 1); }

What is a pointer in C and how is it used?

• A pointer in C is a variable that holds the address of another variable, used for direct memory access and manipulation.

• A pointer in C is a variable that stores a string of characters.

• A pointer in C is used exclusively for file handling operations.

• A pointer in C is a type of function that returns a value.

How do you allocate memory dynamically in C?

• Use printf() to allocate memory.

• Use malloc(), calloc(), or realloc() functions from stdlib.h to allocate memory dynamically.

• Use strcpy() to allocate memory.

• Use free() to allocate memory.

What is the purpose of the 'fopen' function in file handling?

• To close an already opened file.

• To delete a file from the system.

• To open a file for reading or writing.

• To create a new file without opening it.

Explain the use of preprocessor directives in C.

• Preprocessor directives in C are used for file inclusion, macro definition, and conditional compilation.

• Preprocessor directives are used for memory management.

• Preprocessor directives are only for debugging purposes.

• Preprocessor directives are used to define data types.

What is the difference between 'while' and 'do while' loops?

• 'while' loops require a counter, while 'do while' loops do not.

• The main difference is that 'while' checks the condition before execution, while 'do while' checks after execution.

• 'while' loops can only run once, while 'do while' loops can run multiple times.

• 'while' loops are used for infinite loops, while 'do while' loops are for conditional loops.

How can you pass an array to a function in C?

• You must use a struct to pass an array to a function.

• You can only pass arrays by value in C.

• You can pass an array by copying it to a new array inside the function.

• You can pass an array to a function by using a pointer to its first element as a parameter.