C++返回引用的函数例程

//函数返回值为引用
#include <iostream.h>

int a[]={1,3,5,7,9};
int &index(int);    //声明返回引用的函数

void main()
{    
    cout<<index(2)<<endl;
    index(2)=25;
    //a[2] = 25;
    cout<<index(2)<<endl;
}

//引用就是变量的别名,这里是返回一个别名,一个变量的别名
int &index(int i)
{    
    return a[i];  
}

//引用举例
#include <iostream>
using namespace std;

int &max(int &num1,int &num2);
int &min(int &num1,int &num2);

void main()
{
    int n1,n2;
    cout<<"Enter two numbers:";
    cin>>n1>>n2;
    max(n1,n2) = 0;
    cout<<"\nAftrer putting zero in largest,then numbers are:"
        <<n1<<" and "<<n2<<endl;
    cout<<"Enter two numbers:";
    cin>>n1>>n2;
    min(n1,n2)=0;
    cout<<"\nAftrer putting zero in smallest,then numbers are:"
        <<n1<<" and "<<n2<<endl;
}

int &max(int &num1,int &num2)
{
    return (num1>num2?num1:num2);

}

int &min(int &num1,int &num2)
{
    return (num1<num2?num1:num2);
}