class的大小

#include <stdio.h>

class x
{

};

class cx
{
public:
	cx()
	{

	}
	~cx()
	{

	}
};

class cxHasVal
{
public:
	cxHasVal()
	{

	}
	~cxHasVal()
	{

	}
	int a;
	char y;
	
};

class cxHasValFunc
{
public:
	cxHasValFunc()
	{

	}
	~cxHasValFunc()
	{

	}
	int a;
	char y;
	int getASize()
	{
		return sizeof(a);
	}
	void setA()
	{
		a  = 5;
	}
};

int main()
{
	x emptyX;
	int emptySize = sizeof(x);
	printf("size of empty class is %d\n\n",emptySize);

	cx *classx = new cx();
	int clsizePt = sizeof(classx);
	int clsize = sizeof(cx);
	printf("size of class point is %d\n",clsizePt);
	printf("size of class is %d\n\n",clsize);

	cxHasVal *hasVal = new cxHasVal();
	hasVal->a = 12;
	int hasValSize = sizeof(hasVal);
	int rVal = sizeof(cxHasVal);
	printf("size of class Point has val is %d\n",hasValSize);
	printf("size of class has val is %d\n\n",rVal);

	cxHasValFunc *hasValFunc = new cxHasValFunc();
	int hasValFuncSize = sizeof(hasValFunc);
	int rValFunc = sizeof(cxHasValFunc);
	printf("size of class Point has val is %d\n",hasValFuncSize);
	printf("size of class has val Func is %d\n\n",rValFunc);

	return 0;
}