title: LNK2005 and LNK1169 when trying to compile program in Visual Studio 2019
body: <p>I have no experience with C/C++. I do not know how to even open files. I am working with SLN files in Visual Studio 2019 trying to compile a program I took off of GitHub (<a href="https://github.com/Marlowe97/Expected-Force" rel="nofollow noreferrer">https://github.com/Marlowe97/Expected-Force</a>).</p>
  <p>I get these two errors (LNK2005, 'main already defined in TestExpectedForce.obj, and LNK1169 'one or more multiply defined symbols found') when trying to compile the Expected Force solution. The only changes I've made from the downloaded files are the ones directly stated in the instructions on the GitHub page of the program.</p>
  <p>Is there someone who can tell me what to look for in as plain of a way as possible? I know basic Python and R so I understand some terms, but I know nothing about C so no other posted solutions to these errors make any sense to me. I'm already pretty concerned that I'm getting errors after following the step by step instructions from GitHub on what seemed to be a pretty basic task.</p>