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#include<iostream>
using namespace std;

//无参无返
void canshu1()
{
	cout << "该参数为" << endl;
}

//有参无返
void canshu2(int a)
{
	cout << "该参数为"<< a << endl;
}

//无参有返
int canshu3()
{
	cout << "该参数为"  << endl;
	return 999;                  //这里的话就给了canshu3返回值了999，也就是说它的常量为999
}

//有参有返
int canshu4(int a)
{
	cout << "该参数为" << a << endl;
	return a;                    //返回的参数是它本身           
}


int main()
{
	canshu1();


	canshu2(99);


	int num1 = canshu3();         //给参数返回数据
	cout << "num1=" << num1 << endl;
	

	int num2 = canshu4(9999);     //给参数传输数据
	cout << "num2=" << num2 << endl;
	

	system("pause");
	return 0;
}