I know an easy way to create flowchart from source code, there is code to flowchart converter software online, it could help you generate flowchart or NS chart from C, C++, VC++ (Visual C++ .NET) and Delphi (Object Pascal) programming files. You may download it from the official website and try it for free. The Code Flowchart Creator official website is:
http://flowchart-creator.com