android studio 2.3.1 - Error : I am new to android programming.  I have an issue, my pc shutdown  while  Iwa working ona program.

When I turned it on I get all kinds of errors...  I tried other programs which I created in my lesson (which I took from Internet)

None of them work now.  They all give me errors many of them... 
for example...

[image code sample][1]


  [1]: https://i.stack.imgur.com/9Waei.jpg

I think when the PC shutdown I might have lost something,  but I unistalled ANdroid and reinstalled  and I get the same thing...

Thanks  for any help ....


Peter Fraga


