java/W7/ScoreAverage.java

package W7;

public class ScoreAverage {
    public void main(String[] args){
        String filePath = "scores.txt";
        int sum = 0;
        int count = 0;
        try (BufferedReader br = new BufferedReader(new FileReader(filePath))){
            String line;
            while ((line = br.readLine()) != null){
                line=line.trim();
                if (line.isEmpty()){
                    continue;
                }
                try{
                    int score=Integer.parseInt(line);
                    sum += score;
                    count++;
                }catch (NumberFormatException e){
                    System.err.println("无效的数字：" + line);
                }
            }
            if (count==0){
                System.out.println("文件中没有有效成绩");
            }else{
                double average = (double) sum / count;
                System.out.println("平均成绩为：" + average);
            }
        }catch (FileNotFoundException e){
            System.err.println("文件不存在：" + filePath);
        }catch (IOException e){
            System.err.println("读取文件时出错：" + e.getMessage());
        }
    }
}