应用背景使用了简单的显示格式，对计算步长有严格限制，但程序编写简单。欢迎就算法，编程等问题交流
参考文献：Problem 1 (p.446), chapter 9, Computational Fluid Dynamics, The Basics with Applications, John D. Anderson, JR. McGraw-Hill, 2002, 4关键技术编写的一个简单程序，用于计算水力学学习。非守恒型控制方程，显式中心差算法。
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