c++函数三种传递方式

这里我会带大家了解c++中函数的三种传递方式

我们以swap（交换）函数为例：

int tem = a;
	a = b;
	b = tem;

第一种，值传递：

用形参接收实参的值进行操作，对实参没有影响

eg：

#include<iostream>
using namespace std;
void swap(int a,int b)
{
	int tem = a;
	a = b;
	b = tem;
}
int main()
{
	int a = 10;
	int b = 20;
	cout << "交换前" << endl;
	cout << "a=" << a << endl;
	cout << "b=" << b << endl;
	swap(a, b);
	cout << "交换后" << endl;
	cout << "a=" << a << endl;
	cout << "b=" << b << endl;
	system("pause");
	return 0;
}

第二种，地址传递： 

将实参的地址传过去，从而改变实参的值

#include<iostream>
using namespace std;
void swap(int* a,int* b)
{
	int tem = *a;
	*a = *b;
	*b = tem;
}
int main()
{
	int a = 10;
	int b = 20;
	cout << "交换前" << endl;
	cout << "a=" << a << endl;
	cout << "b=" << b << endl;
	swap(&a, &b);
	cout << "交换后" << endl;
	cout << "a=" << a << endl;
	cout << "b=" << b << endl;
	system("pause");
	return 0;
}

第三种，引用传递：

就我自身而言了，认为只是最简单的一种方式，实现实参的改变。

#include<iostream>
using namespace std;
void swap(int& a,int& b)
{
	int tem = a;
	a = b;
	b = tem;
}
int main()
{
	int a = 10;
	int b = 20;
	cout << "交换前" << endl;
	cout << "a=" << a << endl;
	cout << "b=" << b << endl;
	swap(a, b);
	cout << "交换后" << endl;
	cout << "a=" << a << endl;
	cout << "b=" << b << endl;
	system("pause");
	return 0;
}

希望能给与大家帮助。