Java二维数组输入输出

 public static void main(String[] args) {
        int [][] b = {{1,2,3},{1,2,3},{1,2,3}};
        for (int i = 0; i < b.length; i++) {
            for (int j = 0; j < b.length; j++) {

                System.out.print(b[i][j]);
            }
            System.out.println();
        }


        int [][] a = new int[3][3];
        for (int i = 0; i < a.length; i++) {
            for (int j = 0; j < a.length; j++) {
                a[i][j] = j;
            }
        }
        for (int i = 0; i < a.length; i++) {
            for (int j = 0; j < a.length; j++) {
                System.out.print(a[i][j]);
            }
            System.out.println();
        }
    }