1． 用类编写并测试3×3矩阵转置函数，并且使用数组保存转置后的矩阵，要求使用动态内存分配方法。P206，例题6-5，6-17，6-26，27-1. Written and tested with a class of 3 × 3 matrix transpose function, and after using the array containing the transposed matrix, requires the use of dynamic memory allocation.