初学者的问题-为什么C使用*声明指针而不使用＆？

由任性发布于 2020-05-18 08:10:57

所以说：

int n = 50;
int *p = &n;

Why do we use * and not & in C? What's the key difference between * and &?

一手的触碰 2020-05-18 08:10:58

Using * to declare pointers is mostly a matter of convention, but there is a reason of consistency: the * in the declaration int *p means int is the type of *p.

It might seem more consistent to write int &p = &n as p is initialized to the address of n but this convention would not hold for double pointers: int **pp defines pp as a pointer to a pointer to an int, yet pp cannot be initialized with &(&n).

Rabbit_19C 2020-05-18 08:10:58

In C * in a variable definition means "pointer to". In an expression the & operator means "address of", while * operator means "dereference".

所以实际上：

int n = 1;
int* p = &n; // Create a pointer and initialize with the address of n

if (*p == 1) {
  // This is true when dereferencing the pointer
}

Why not use & as in int& p? Mostly because the syntax isn't set up that way.

It's worth noting that in C++ the & comes back to mean "reference":

int n = 1;
int& r = n;

请注意，无需进行任何特殊处理，只需弄清楚即可。

QQ企鹅 2020-05-18 08:10:58

在像c或c ++这样的编程语言中，我们有指针*和地址＆。

何时以及如何使用：

int a=5;
int b=a; //b=  5
int c=&a; //c= address of a variable 
int *d=&a; //d is a 

If we change **b** to another number **a** will be not changed.
But if change **d** to another number **a** will be changed.

实际上，我们将指针用于对象，列表等。使用指针，您不会消耗大量内存。库使用指针对数据进行操作，而无需在内存中创建新位置。

任性

这家伙很懒，什么都没留下

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