函数传参的三种方式

#include
void swap1(int x, int y)//定义中的x,y变量是swap函数的两个形参
{
	int tmp;
	tmp = x;
	x = y;
	y = tmp;
	printf("x=%d,y=%d\n", x, y);
}
int main()
{
	int a = 2;
	int b = 3;
	swap1(a, b);//a,b变量为swap函数的实际参数
	printf("a=%d,b=%d", a, b);
	return 0;
}

void swap2(int *px, int *py)
{
	int tmp;
	tmp = *px;
	*px = *py;
	*py = tmp;
	printf("px=%d,py=%d\n", *px, *py);
}
int main()
{
	int a = 2;
	int b = 3;
	swap2(&a, &b);/*调用了swap函数，同样也有隐含动作px=&a;py=&b;*/
	printf("a=%d,b=%d", a, b);
	return 0;
}

#include
void  swap3(int &x,int &y)
{
	int tmp = x;
	x = y;
	y = tmp;
	printf("x=%d,y=%d\n", x, y);
}
int main()
{
	int a = 2;
	int b = 3;
	swap3(a, b);//调用方式与传值一样
	printf("a=%d,b=%d", a, b);
	system("pause");
	return 0;
}