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

public class ScoreAverage {
    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) {
                line = line.trim();
                if (line.isEmpty()) continue;
                
                try {
                    sum += Integer.parseInt(line);
                    count++;
                } catch (NumberFormatException e) {
                    System.err.println("无效成绩：" + line);
                }
            }

            if (count > 0) {
                double avg = (double) sum / count;
                System.out.println("平均分：" + avg);
            } else {
                System.out.println("无有效成绩数据");
            }

        } catch (IOException e) {
            System.err.println("文件读取失败：" + e.getMessage());
        }
    }
}