Which function would you use to compare two strings lexicographically in C?
- strcat()
- strcmp()
- strcpy()
- strlen()
You would use the strcmp() function to compare two strings lexicographically in C. It returns 0 if the strings are equal, a positive value if the first string is greater, and a negative value if the second string is greater.
Using the ________ function, the file pointer can be moved to the end of a file.
- fseek()
- rewind()
- ftell()
- fsetpos()
The correct option is fseek(). This function is used to set the file position indicator to a specific position within the file. When the SEEK_END constant is provided as the reference point, it moves the file pointer to the end of the file, allowing operations like appending data.
In a graphics rendering engine, you need to apply different transformations (e.g., rotate, scale, translate) to objects. How can function pointers be used to simplify the implementation?
- Define a function pointer for each transformation type
- Use if-else statements to select transformations
- Use global variables to store transformation functions
- Implement each transformation directly in the code
Option A is the correct answer. By defining a function pointer for each transformation type, you can easily switch between different transformations without altering the engine's core logic. Options B, C, and D are less flexible and efficient. Option A simplifies the code.
The ______ function in C can be used to change the position of the file pointer in a stream.
- fmove()
- fseek()
- fileptr()
- fposition()
The correct option is b) fseek(). This function is used to set the file position indicator for the specified stream, allowing you to move the file pointer to a specific location.
You are working on a program that simulates a chessboard. How would you represent the chessboard using arrays?
- 1D Array
- 2D Array
- Hash Table
- Linked List
A chessboard is best represented using a 2D array because it provides a grid structure, allowing easy indexing for each square.
How do you declare a pointer variable in C?
- Using the % operator
- Using the & operator
- Using the * operator
- Using the -> operator
In C, you declare a pointer variable using the * operator. For example, int *ptr; declares a pointer to an integer.
How does the 'extern' keyword affect the scope and lifetime of a variable in C?
- It doesn't affect the scope or lifetime of a variable.
- It extends the scope and lifetime of a variable.
- It extends the scope but reduces the lifetime of a variable.
- It reduces the scope but extends the lifetime of a variable.
In C, the 'extern' keyword extends the scope of a variable but reduces its lifetime. It allows a variable declared outside a function to be used within that function, but the variable's lifetime remains outside the function.
How are strings typically terminated in C?
- With a comma
- With a newline character
- With a null character ( ' ' )
- With a space character
Strings in C are typically terminated with a null character (' ') to indicate the end of the string.
What is the default starting value of an enumeration in C?
- 0
- 1
- The value of the first enumeration constant
- Unspecified
In C, if no initial value is provided for the first enumeration constant, it starts with 0. Subsequent constants increment by 1.
In C, what is the difference in memory allocation between character arrays and string literals?
- Character arrays are automatically null-terminated, while string literals are not.
- Character arrays are stored in read-write memory, while string literals are stored in read-only memory.
- Character arrays cannot be used as function arguments, while string literals can.
- String literals are stored in read-write memory, while character arrays are stored in read-only memory.
Character arrays in C are typically stored in read-write memory, allowing you to modify their contents. In contrast, string literals are stored in read-only memory, making them immutable. This difference in memory allocation is essential for understanding how to work with strings in C.