采用模态叠加法和Newmark方法求解悬臂梁的响应，可以直接运行，经验证程序正确-Modal superposition method and Newmark method for solving cantilever response, and can directly run the program properly validated

使用模态叠加法求解在基础激励下的悬臂梁端部的挠度(Use the modal superposition method to solve the deflection of the cantilever beam end under fundamental excitation)