【C++】三种函数参数传递（值传递、地址传递、引用传递）

• 特点：形参的变化不改变实参的值
• 定义：func(int a, int b)
• 调用：func(a,b);
  
  

• 形参的变化会改变实参的值
• 定义：func(int *a, int *b)
• 调用：func(&a,&b);
  
  

• 形参的变化会改变实参的值
• 定义：func(int &a, int &b)
• 调用：func(a,b);
  
  

#include
using namespace std;

//值传递
void valueTrans(int a, int b)
{
      int temp = a;
      a = b;
      b = temp;
}
// 地址传递
void addrTrans(int *a, int *b)
{
      int temp = *a;
      *a = *b;
      *b = temp;
}

// 引用传递
void citeTrans(int &a, int &b)
{
      int temp = a;
      a = b;
      b = temp;
}


int main()
{
      int a = 10;
      int b = 20;
      
      valueTrans(a,b);	//值传递，不改变实参
      cout <<"值传递"<< endl;
      cout <<"a = " << a << endl;
      cout <<"b = " << b << endl;

      addrTrans(&a, &b);	//地址传递，改变实参
      cout <<"地址传递" << endl;
      cout <<"a = " << a << endl;
      cout <<"b = " << b << endl;

      citeTrans(a, b);	//引用传递，改变实参
      cout <<"引用传递" << endl;
      cout <<"a = " << a << endl;
      cout <<"b = " << b << endl;
      
      return 0;
}