定义两3*3数组，分别输出矩阵之和跟相乘的结果，代码如下：public class Problem { public static void main(String[] args){ int arrayA[][]={{1,2,3},{4,5,6},{7,8,9}};int arrayB[][]={{1,2,3},{4,5,6},{7,8,9}};int arrayC[][] = new int[3][3];int arrayD...