C Programming Challenge

What are the basic data types available in C?

• array

• int, float, double, char, void

• string

• boolean

Explain the difference between local and global variables in C.

• Local variables are declared outside functions; global variables are declared inside functions.

• Local variables are function-scoped; global variables are accessible throughout the program.

• Local variables can be accessed globally; global variables are limited to functions.

• Local variables retain their values between function calls; global variables do not.

How do you declare an array in C?

• int arr[10];

• arr int[10];

• int[10] arr;

• array int[10];

What is the purpose of the 'void' keyword in a function declaration?

• The 'void' keyword is used to indicate a pointer type.

• The 'void' keyword specifies the function's return type.

• The 'void' keyword allows a function to accept any number of parameters.

• The 'void' keyword indicates that a function does not return a value.

How can you read data from a file in C?

• Use printf() to display data directly from the file.

• Read data using the read() function without opening the file.

• Use fopen() to open the file, then fgets() or fscanf() to read data, and fclose() to close the file.

• Close the file before reading any data from it.

What is a string in C and how is it represented?

• A string in C is a single character.

• A string in C is a fixed-length integer.

• A string in C is a list of numbers.

• A string in C is an array of characters ending with a null character ('\0').

Describe the use of pointers in functions.

• Pointers can only be used with arrays.

• Pointers prevent functions from accessing global variables.

• Pointers are used to create new variables in functions.

• Pointers enable functions to modify variables directly and improve efficiency by avoiding data copying.

What is the significance of the 'return' statement in a function?

• The 'return' statement is significant because it allows a function to output a value and terminate its execution.

• The 'return' statement can be used to pause a function's execution.

• The 'return' statement is only necessary for void functions.

• The 'return' statement is used to define a function's name.

How do you open a file for writing in C?

• fopen('filename.txt', 'r');

• open('filename.txt', 'w');

• fopen('filename.txt', 'a');

• fopen("filename.txt", "w");

What is the difference between a character array and a string in C?

• A character array can only hold numeric values, while a string can hold characters.

• Strings are defined as fixed-size arrays, whereas character arrays can be dynamic.

• A string can be modified while a character array cannot.

• A character array is not necessarily null-terminated, while a string is a null-terminated character array.