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 },    };    int count = 0;    int sum = 0;    // 方法1    for (int[] i : scores){        for (int n : i){            count++;            sum += n;        }    }    double average = 0;    average = (double)sum/count;    System.out.println(average);    if (Math.abs(average - 77.733333) < 0.000001) {        System.out.println("测试成功");    } else {        System.out.println("测试失败");    }}