What does *a mean in c++
*a in C represents a pointer reference, pointing to the memory address of variable a. This pointer can be used to access and modify variable values, dynamically allocate memory, and create data structures.
*a in C
In the C programming language, *a represents a pointer reference to variable a.
The meaning of pointer
A pointer is a special type of variable that stores the memory address of another variable. This allows you to access and modify the value of other variables through pointers.
Grammar
*a’s syntax is as follows:
type *variable_name;
where:
type
Is the type of variable pointed to by the pointer.variable_name
is the name of the pointer variable.
Usage
*a can be used for the following purposes:
- Access and modify the value of a variable without directly referencing the variable .
- Dynamically allocate memory.
- Create data structures such as linked lists and trees.
Example
The following code creates a pointer to the integer variable a:
int a = 10; int *ptr = &a;
Now, it can be accessed and modified through the pointer ptr Variable a:
*ptr = 20; // 将 a 的值更改为 20 int value = *ptr; // 获取 a 的值,该值为 20
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