C Programming Challenge

What is the syntax to declare a pointer in C?

• int *ptr;

• char *ptr;

• double *ptr;

• void *ptr;

Explain the difference between 'malloc' and 'calloc' functions in C.

• malloc allocates uninitialized memory block, calloc allocates initialized memory block with all bits set to zero

• malloc allocates memory in stack, calloc allocates memory in heap

• malloc is used for allocating memory for arrays, calloc is used for allocating memory for variables

• malloc and calloc are interchangeable functions in C

How do you pass arguments by reference in C?

• Pass the address of the variable as an argument to the function and dereference the pointer inside the function to access and modify the original variable.

• Pass the value of the variable as an argument to the function

• Use a global variable to pass arguments by reference

• Pass a copy of the variable to the function

What is the purpose of the 'sizeof' operator in C?

• To calculate the square root of a number

• To convert a variable to a different data type

• To determine the size in bytes of a data type or a variable.

• To check if a variable is initialized

Explain the difference between 'while' and 'do-while' loops in C.

• Both 'while' and 'do-while' loops have the same behavior

• In 'while' loop, the condition is checked after executing the block of code

• In 'while' loop, the condition is checked before executing the block of code, whereas in 'do-while' loop, the block of code is executed at least once before checking the condition.

• In 'do-while' loop, the block of code is executed only if the condition is true

What is the 'switch' statement used for in C?

• It is used for creating loops in C.

• It is used for defining variables in C.

• It is used for multi-way branching based on the value of a variable or expression.

• It is used for handling exceptions in C.

How do you dynamically allocate memory in C?

• pointer_variable = (cast-type*) calloc(size);

• pointer_variable = (cast-type*) malloc(size);

• pointer_variable = (cast-type*) free(size);

• pointer_variable = (cast-type*) realloc(size);

What is the purpose of the 'typedef' keyword in C?

• It is used to declare variables

• It is used to create an alias for data types.

• It is used to define new functions

• It is used to control program flow

Explain the concept of 'recursion' in C.

• Recursion in C is a variable type

• Recursion in C is a loop structure

• Recursion in C is a programming technique where a function calls itself directly or indirectly.

• Recursion in C is a data structure

What is the difference between 'local' and 'global' variables in C?

• Local variables are declared outside of any function and have global scope, while global variables are declared within a function and have local scope.

• Local variables can be accessed from any part of the program, while global variables are limited to the function they are declared in.

• Local variables are declared with the 'global' keyword, while global variables are declared with the 'local' keyword.

• Local variables are declared within a function and have local scope, while global variables are declared outside of any function and have global scope.