In a C program that manipulates a large dataset, you observe that the performance is significantly reduced when passing data between functions. How could pointers be used to improve the performance?
- Pointers can be used to create additional datasets.
- Pointers can be used to pass data by reference.
- Pointers can be used to pass data by value.
- Pointers can't improve performance in this scenario.
Pointers can be used to pass data by reference, which avoids the overhead of copying large datasets, improving performance in data manipulation tasks.
What is the purpose of the #pragma directive in a C program?
- It controls compiler-specific behaviors.
- It has no specific purpose in C programming.
- It is used to define custom macros in the code.
- It is used to include external libraries in the code.
The #pragma directive in C is used to control compiler-specific behaviors, such as optimization settings and platform-specific configurations.
In the context of C programming, what is the size of an 'enum' data type?
- 2 bytes
- 4 bytes
- It depends
- Varies
The size of an 'enum' data type varies in C, and it depends on the specific implementation. Typically, it's large enough to represent all the enumeration constants.
The typedef keyword in C is used to create an ________ for existing data types.
- Alias
- Enumeration
- Function
- Pointer
In C, the typedef keyword is used to create an alias for existing data types, making code more readable and maintainable by providing descriptive names.
What is the relationship between the addresses of consecutive elements in a one-dimensional array?
- Addresses are assigned based on the element's value
- Addresses are the same for all elements
- Consecutive elements have addresses in random order
- Consecutive elements have consecutive addresses
In a one-dimensional array, consecutive elements have consecutive addresses. The address of each element is one unit (e.g., byte) greater than the previous element.
The keyword ________ is used in C to define a constant.
- constant
- define
- identifier
- value
In C, the keyword 'const' is used to define a constant. It is used to declare variables as constant, and their values cannot be changed after declaration.
An array of strings in C can be declared as a ________.
- 2D array
- grid
- matrix
- stack
An array of strings in C can be declared as a 2D array. Each row of the 2D array represents a string, and you can have multiple strings stored within the same data structure.
The typedef keyword can be used to simplify the declaration of ________ in C.
- Data structures
- Functions
- Macros
- Variables
The typedef keyword in C is commonly used to simplify the declaration of user-defined data structures, making it easier to work with complex data types.
The function ________ can be unsafe to use as it does not check for buffer overflow while reading a string in C.
- fgets
- getchar
- gets
- scanf
The correct answer is fgets. gets is unsafe due to buffer overflow issues, scanf can be problematic when not used carefully, and getchar is used for character input, not strings. fgets is a safer choice for reading strings.
The keyword ________ is used to declare a variable that retains its value between successive calls to the functions in which it is declared.
- auto
- extern
- register
- static
In C, the static keyword is used to declare a variable that retains its value between successive calls to the functions in which it is declared. This keyword is used to create a local variable with a persistent value, maintaining its state across function calls.