输入一个班学生大学计算机基础成绩记录显示所有成绩记录 计算并输出平均成绩,均方差输出成绩与排名结果存入文件chengji.txt 输入一个班学生大学计算机基础成绩记录显示所有成绩记录 计算并输出平均成绩,均方差输出成绩与排名结果存入文件chengji.txt<<隐藏 -Students enter a college computer records show that all results based on performance records　calculate and output the average score, standard deviation score and ranking output documents chengji.txt enter into a class based on student performance Computer records show that all performance records　calculate and output average scores, standard deviation score and ranking results into the output file chengji.txt < < hide