The difference between *a and a in c language

In C language, a is a pointer to the memory address of variable a, and a is an ordinary variable. a stores the value in a, and a stores the value of itself. a accesses the value pointed to by dereferencing it, while a accesses its own value directly. &a returns the memory address of a, while a returns the memory address pointing to the value.

The difference between *a and a in c language

In c language, *a and a are two different concepts. The main differences between them are as follows:

• Type: *a is a pointer toa is a pointer to the memory address of a variable; and a is an ordinary variable.
• Value: The value of *a is the value stored in the a variable; and the value of a itself.
• Operation: *a can access the value it points to through the dereference operator (*); and aOnly its own value can be accessed directly.
• Address: &a returns the memory address of the a variable; and *a returns the a variable The memory address of the stored value.

Detailed explanation:

• Pointer (*a): Pointer is a data type that points to the memory address of a variable . *a represents a pointer to the memory address of variable a. The value stored at that memory address can be accessed through the dereference operator (*).
• Variable (a): A variable is a named memory location that can store a value. a represents an ordinary variable, which stores a specific value.
• Dereference: The dereference operator (*) is used to access the value pointed to by the pointer. For example, *a means taking the value stored in the memory address pointed to by the a pointer.
• Address operator: Address operator (&) is used to obtain the memory address of a variable. For example, &a returns the memory address of the a variable.

Example:

int a = 10;
int *p = &a;

printf("变量 a 的值：%d\n", a);
printf("指向 a 的指针 p 的值：%d\n", *p);

Output:

<code>变量 a 的值：10
指向 a 的指针 p 的值：10</code>

In this example, a is a stored value of 10 The variable, p is a pointer to the memory address of the a variable. *p Dereference the pointer and return the value stored in the a variable, which is 10.

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