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

public class ScoreAverageCalculator {
    public static void main(String[] args) {
        String filePath = "scores.txt";
        int sum = 0;
        int count = 0;

        // 使用 try-with-resources 确保流自动关闭
        try (BufferedReader br = new BufferedReader(new FileReader(filePath))) {
            String line;
            while ((line = br.readLine()) != null) {
                // 跳过空行
                if (line.trim().isEmpty()) {
                    continue;
                }
                try {
                    int score = Integer.parseInt(line.trim());
                    sum += score;
                    count++;
                } catch (NumberFormatException e) {
                    // 数字格式错误：记录并跳过该行
                    System.err.println("数字格式错误，跳过无效数据: " + line);
                }
            }

            // 计算并输出平均分
            if (count > 0) {
                double average = (double) sum / count;
                System.out.println("有效成绩数量: " + count);
                System.out.println("总分: " + sum);
                System.out.printf("平均分: %.2f\n", average);
            } else {
                System.out.println("没有有效的成绩数据");
            }

        } catch (java.io.FileNotFoundException e) {
            // 文件不存在异常
            System.err.println("错误: 文件 " + filePath + " 不存在，请检查文件路径");
        } catch (IOException e) {
            // 读取错误异常
            System.err.println("错误: 读取文件时发生异常 - " + e.getMessage());
        }
    }
}