运行出错

求救运行出错
#include <iostream>
using namespace std;
viod main()
{
int a;
int &ra=a;
a=5;
cout<<"a="<<a<<"\n";
cout<<"ra="<<ra<<"\n";
cout<<"a的地址是："<<&a<<"\n";
cout<<"ra的地址是："<<&ra<<"\n";
int b=8;
ra=b;
cout<<"a="<<a<<"\n";
cout<<"b="<<b<<"\n";
cout<<"ra="<<ra<<"\n";
cout<<"a的地址是："<<&a<<"\n";
cout<<"b的地址是："<<&b<<"\n";
cout<<"ra的地址是："<<&ra<<"\n";
}




[解决办法]
都编译不过去吧，引用一旦赋值了就不能改变了，只可能是一个变量的别名。