C Programming Exercises

A sequence of characters, often used to represent text or data within a program.

A predefined block of reusable code that performs a specific task. It can accept inputs (arguments) and return a value.

A data structure that holds a fixed-size collection of elements of the same data type, accessed using an index.

A loop that iterates a specific number of times, controlled by a counter that increments or decrements.

A loop that continues to iterate until a specific condition is met.

A library function is a pre-written function that is already available in a compiler package. It performs a specific task and can be directly called in your program.

A user-defined function is created by the programmer to perform a specific task. It is customized to meet the specific needs of the program.

A variable declared inside a function or block (for example, an 'if' or 'for' block). It can only be accessed within that specific function or block.

A variable declared outside of any function. It can be accessed from any part of the program and shared between functions.

A function that does not return any value. It performs a specific task, but does not send back a result after execution.

The process of converting rows into columns and vice versa in a matrix. It involves interchanging the positions of elements in a matrix.

A data structure used to store elements in rows and columns, forming a rectangular array.

A loop that executes the loop's code before checking a condition, guaranteeing at least one execution.

A control flow statement that allows you to choose between different code blocks based on the value of a variable.

A statement that allows a program to choose a specific block of code to execute based on the value of a variable.

A special variable that stores the memory address of another variable or data structure. It allows direct access to the data without needing to copy it.

A method that allows a program to pass data to a function or method as an argument. This lets the function manipulate the original data in memory.

A pointer variable is declared with the * operator, indicating that it holds a memory address.

The ampersand (&) symbol is used to access the memory address of a variable.

Pointers need to have a corresponding data type that matches the variable they point to.

You can access the variable that a pointer references using the * operator along with the pointer name, similar to dereferencing.

Pointers allow efficient modification of data by directly changing the value at the memory location they point to.

The assignment operation '=' copies the address of one variable to the pointer variable.

Pointers are essential for dynamic memory allocation, linked lists, and other advanced programming concepts.

Direct access refers to using the variable name directly to access its value.

Indirect access uses a pointer to access the value of a variable.

Pointer arithmetic allows you to perform mathematical operations on pointers, primarily addition and subtraction.

When you increase a pointer value by 1, the pointer points to the next data element in memory. This movement corresponds to the size of the data type.

You can change the value of a pointer, which will also modify the value of the original variable it points to.

The asterisk (*) operator is used to dereference a pointer, meaning it retrieves the value stored at the memory address pointed to by the pointer.

A function that does not return any value. It performs a specific task but doesn't send back a result.

A pointer variable is declared using the * operator. It holds a memory address of another variable or data structure, allowing direct data access without copying.

The ampersand (&) symbol is used to obtain the memory address of a variable. It allows you to access the location where the variable's data is stored.

Pointers have a data type that matches the type of variable they point to. This ensures data consistency and prevents errors when accessing stored values.

To access the value stored at the location pointed to by a pointer, use the dereferencing operator (*). It retrieves the value at the address.

Pointers can efficiently modify data directly. By changing the value at the memory location they point to, you modify the original variable.

The assignment operator (=) copies the memory address of one variable into a pointer variable. The pointer now points to that specific location.

Pointers are crucial for dynamic memory allocation, allowing programs to manage memory efficiently. They are also used in linked lists and other data structures.

The sizeof() operator in C returns the size of any data type, expression, array, etc. It takes the data type or expression as an argument and returns the result, which is the size of that data type in bytes.

When a pointer is incremented, it moves to the next memory location, which is determined by the data type it points to. So, if it points to an int, it will move 4 bytes (assuming int is 4 bytes in your system).

This statement increments the pointer p and then dereferences the new address it points to. So, you're accessing the value at the next memory location.

This statement dereferences the pointer p and then increments the value it points to. So, you're directly modifying the data at that memory address.

This statement dereferences the pointer p and then increments the value it points to. The value is incremented after it's been used.

When you pass a pointer as a parameter to a function, the function can directly modify the original variable that the pointer points to. This is because the pointer is essentially a reference to the location of the data in memory.

The expression *ptr *= 2.54 multiplies the value pointed to by the pointer ptr by 2.54. The * before the pointer dereferences it, while the *= operator combines multiplication and assignment. So, this statement converts a value originally in inches to centimeters, modifying the value in place.

In this code example, the function test() takes two integer parameters. It likely modifies the original values passed to it by directly accessing the memory locations using pointers. This allows for the function to directly alter the original data without making copies.