import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
import java.io.FileNotFoundException;

public class ScoreCalculator {
    public static 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) {
                try {
                    int score = Integer.parseInt(line.trim());
                    sum += score;
                    count++;
                } catch (NumberFormatException e) {
                    System.out.println("警告：跳过无效的数字格式 - \"" + line + "\"");
                }
            }

            if (count == 0) {
                System.out.println("未找到有效的成绩数据");
            } else {
                double average = (double) sum / count;
                System.out.println("========== 成绩统计结果 ==========");
                System.out.println("有效成绩数量: " + count);
                System.out.println("总成绩: " + sum);
                System.out.println("平均分: " + String.format("%.2f", average));
            }

        } catch (FileNotFoundException e) {
            System.out.println("错误：文件不存在 - " + filePath);
            System.out.println("请确保 scores.txt 文件位于程序运行目录下");
        } catch (IOException e) {
            System.out.println("错误：文件读取失败 - " + e.getMessage());
        }
    }
}