引用(reference)

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#include <iostream>
using namespace std;
int main (){
   int variable=3;
   int &alias=variable; //定义一个引用变量alias，aliase相当于variable的别名，使用alias就是使用variable.
                        //引用变量alias必须在定义时初始化，以后也不可以通过alias=b之类的改变为变量b的引用.                   
   int *pointer;
   pointer=&alias;
   cout<<&variable<<endl;
   cout<<&alias<<endl;
   cout<<pointer<<endl;   //程序中variable, alias,pointer都指向了一个地址
   cout<<variable<<" "<<alias<<endl;
   variable++;    
   cout<<variable<<" "<<alias<<endl;
   alias++;
   cout<<++alias<<" "<<variable<<endl;
}

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#include <iostream>
using namespace std;

void SwapVarible(int a,int b);
void SwapPointer(int *fa,int *fb);
void SwapReference(int &ra,int &rb);
int main (){
    int a=10,b=20;
    SwapVarible(a,b);
    cout<<a<<","<<b<<endl;
    SwapPointer(&a,&b);
    cout<<a<<','<<b<<endl;
    SwapReference(a,b);
    cout<<a<<','<<b<<endl;
}
 void SwapVarible(int a, int b){
    int temp=a;
    a=b;
    b=temp;
}
void SwapPointer(int *fa,int *fb){
    int temp;
    temp=*fa;
    *fa=*fb;
    *fb=temp;
}
void SwapReference(int &ra,int &rb){
    int temp;
    temp=ra;
    ra=rb;
    rb=temp;
}