24.定义一个整型变量，赋予1-100值。要求用户猜这个数，比较两数大小，把结果提示给用户，直到猜对为止

#include<iostream>
using namespace std;

int main()
{
int a=50;
int n;
while(1)//关键，造成一个死循环
{
cout<<"please input an number: "<<endl;
cin>>n;
if(a==n)//循环退出条件
{
cout<<"n="<<n<<endl;
break;
}else if(a<n)
{
cout<<"your number are biger than the number,please try again."<<endl;
}else if(a>n)
{
cout<<"your number are smaller than the number,please try again."<<endl;
}
}
return 0;
}