水头损失线性拟合回归编程，计算方法简单精确-Head loss linear fitting regression programming, calculation method is simple and accurate

复杂官网的恒定流计算，采用Hardy Cross方法进行迭代，最后可以得到每个管道的流量和水头损失，程序里面有数据输入操作说明-Constant stream of complex calculations official website, using Hardy Cross iterative methods, and finally you can get traffic and head loss for each pipe, which has a data entry program