由于矩阵连乘不同结合方式的运算工作量很不一样. 工作量相差也非常大；所以要寻找一种最佳的结合方式, 然后再执行矩阵乘法运算-continually multiply matrices combining different ways of computing workload very different. The workload is also very big difference; So to find the best combination of a way, and then th