import java.io.*;

/*原始代码
BufferedReader br=new BufferedReader(new FileReader("score.txt"))
String line;
while((line=br.readLine())!=null){
    sum += Integer.parseInt(line)
}
br.close()
 */


//修改后的代码
public class score {
    public static void main(String[] args){
        //使用try()-with-resources确保文件自动关闭
        try(BufferedReader br=new BufferedReader(new FileReader("score.txt"))){
            double sum=0;
            int count=0;
            String line;
            while((line=br.readLine())!=null){
                try{
                    sum += Integer.parseInt(line);
                    count++;
                } catch (NumberFormatException e) {
                    System.out.println("数字格式错误");
                }
            }

            //计算平均数
            if (count>0){
                double average=sum/count;
                System.out.println("平均分是"+average);
            }
            else{
                System.out.println("计数不符合规范，没有平均数");
            }
        }
        //最外层的catch
        catch (FileNotFoundException e){
            System.out.println("文件不存在");
        }
        //同样也是最外层的catch
        catch (IOException e){
            System.out.println("读取文件发生错误");
        }
    }
}