你的源程序多输出了一些字符,要严格按照题目要求!
还有数据类型处理BUG!

> #include<iostream.h>
> void main()
> { int i=1;
>   float sumout=0,sumin;
>   cout<<"please input the lengh"<<endl;
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    删除
>   cin>>sumin;
>   while(sumin!=0)
>  {
>   for(sumout=0,i=1;sumout<sumin;)
>   {sumout+=float(1/(++i));
     ~~~~~~~~~~~~~~~~~~~~~~~
     更改为sumout+=1/(float)(++i);
>    }
>   cout<<"the number of card is "<<i-1<<endl;
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   更改为cout<<i-1<<" card(s)"<<endl;
>   cin>>sumin;
>  }
> }