怎么样可以实现dl救命

#include <iostream>
using namespace std;
int main()
{
      int score,g;
      cout<<"please input score:<<endl;
      while(scanf("%d",&score) != EOF)
      {
      g = score/10;
      switch(g)
      {
            case 10:
            case 9:
                  cout<<"优秀."<<endl;
                  break;
            case 8:
                  cout<<"良好."<<endl;
                  break;
            case 7:
                  cout<<"中等."<<endl;
                  break;
            case 6:
                  cout<<"及格."<<endl;
                  break;
            default:
                cout<<"差."<<endl;
                break;
       }
       }
       system("pause");
       return 0;
}

用if else 语句配合while循环。