C语言之指针本身的地址、指针指向的地址、指针的指针地址(五十七)

#include 

int main(){
	int a = 5;
	int b = 6;

    //1.指针p存放了变量a的地址，*a = 5；
	int *p = &a;

    //2.指针p存放了变量b的地址，*b = 6；
	int *q = &b;

	int c = 7;
    //3.指针m存放了变量c的地址，*m = 7；
	int *m = &c;

	printf("&a = %pn",&a);
	printf("&b = %pn",&b);
	printf("&c = %pnn",&c);
	
	printf("p = %pn",p);
	printf("q = %pnn",q);

    //4.指针p指向指针q，指针p存放指针q的地址；p和q指向同一个地址&b
	p = q;
	printf("p = %pn",p);
	printf("q = %pnn",q);

    //5.指针q指向指针m，指针q存放指针m的地址;
    //注意：本来指针q指向的是&b的地址，但是被覆盖了，现在指向指针m，即&c的地址;q和m同时指向&c
	q = m;
	printf("p = %pn",p);
	printf("q = %pn",q);
	printf("m = %pnn",m);

    //6.二级指针
	int **t = &m;
    //&m表示：指针m自己本身的地址，赋值给了二级指针t;所以t指向&m，即t保存了&m的地址。
	printf("&m = %pn",&m);
	printf("t = %pn",t);

    //*t:存放的是m指向的地址&c
	printf("*t = %pn",*t);

    //**t：二级解引用，取到的是c的值，等于7.
	printf("**t = %pn",**t);
	
}

打印：

&a = 0x7ffe1e6549ac
&b = 0x7ffe1e6549b0
&c = 0x7ffe1e6549b4

p = 0x7ffe1e6549ac
q = 0x7ffe1e6549b0

p = 0x7ffe1e6549b0
q = 0x7ffe1e6549b0

p = 0x7ffe1e6549b0
q = 0x7ffe1e6549b4
m = 0x7ffe1e6549b4

&m = 0x7ffe1e6549b8
t = 0x7ffe1e6549b8
*t = 0x7ffe1e6549b4
**t = 0x7