Deeply understand the different functions of * and & in C language

The pointer () points to the variable memory address, and the address operator (&) obtains the variable address. Pointers are dereferenced using operators to access values, while address operators return a pointer to the location of a variable. These operators are used for dynamic memory allocation, linked list and array operations.

In-depth understanding of the different functions of * and & in C language

Pointer (*) and address operator (&) are There are two important operators in C language, but they have different functions.

Pointer (*)

A pointer is a variable that points to the address of a variable in memory. By using pointers, we can access the contents of this variable indirectly. Pointers are represented by an asterisk (*).

int x = 10;
int *ptr = &x; // ptr指向变量x的地址

Now, ptr points to the address of x. We can use the * operator to dereference the pointer and access the value of x.

int value = *ptr; // value接收x的值

Address operator (&)

Address operator (&) gets the address of a variable. It returns a pointer to the memory location of the variable.

int x = 10;
int *ptr = &x; // ptr接收x的地址

In this example, ptr will contain the memory address of x.

Practical case

Using pointers and address operators, we can implement many useful functions, such as:

• Dynamic Memory allocation: We can use pointers to manage dynamically allocated memory.
• Linked list: Pointers are used to create and manage linked list structures.
• Array operations: Pointers can be used to traverse and operate arrays.

To understand the difference between pointer and address operators, let’s see an example:

int x = 10;
int *ptr = &x;
int y = *ptr;

In this example:

• ptr is a pointer to x, *ptr is a dereferenced pointer, which contains the value of x, which is 10.
• &x is the address of x, it is not a pointer, so we cannot dereference it.

By understanding the difference between pointer and address operators, we can write more efficient and readable C code.

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