如何判断DataContext有修改: EF6的 using (var db new Model1())
{if (db.ChangeTracker.HasChanges()){Console.WriteLine("Something has changed");}
} EF5中: public bool HasUnsavedChanges(){return this.ChangeTracker.Entries().Any(…
26 最大流 就像我们可以对一个路网构建一个有向图求最短路一样,我们也可以将一个有向图看成是一个"流量网络(flow network)",用它来回答关于流的问题. Just as we can model a road map as a directed graph in order to find the shortest path from one point to a…