if语句转换switch语句

    switch (socre/10)
    {
    case 0:
    case 1:
    case 2:
    case 3:
    case 4:
    case 5:
        grade = 1;
        break;
    case 6:
    case 7:
    case 8:
        grade = 2;
        break;
    default:
        grade = 3;
        break;
    }