public class AverageGrade {
    public static void main(String[] args){
        // 用二维数组表示的学生成绩:        int[][] scores = {
                { 82, 90, 91 },
                { 68, 72, 64 },
                { 95, 91, 89 },
                { 67, 52, 60 },
                { 79, 81, 85 },
        };
        // 计算所有学生的平均分:        int rows = scores.length;
        int sum=0;
        double plustime=0;
//        System.out.println(wild);        for (int i=0;i<rows;i++){
            int col=scores[i].length;
            for (int j=0;j<col;j++){
                sum = sum+scores[i][j];
                plustime++;
            }
        }
        double average = 0;
        average = sum/plustime;
        System.out.println(average);
        //测试：        if (Math.abs(average - 77.733333) < 0.000001) {
            System.out.println("测试成功");
        } else {
            System.out.println("测试失败");
        }
    }
}