#include <iostream.h>
class Score
{private:
    float english_score;
    public:
    void setscore(float i){english_score=i;}
    void printscore()
    {
        cout<<english_score<<endl;
        }
   };
 main()
{ Score stu1;
    stu1.setscore(85.3);
    stu1.printscore();
    stu1.setscore(93.5);
    stu1.printscore();
   
   
}

我用C-FREE编译了一下，没没问题啊！你用的什么编译器啊？