Please format your code using markdown syntax, see: Problem with bool in solve() - #3 by kamensky for details.
It would also help if you could include the whole error message, and in particular which line is causing out of memory error.
Note that your system is fairly small, so I’m curious as to how much RAM you have available on your system.
Also note that we advice new users to use DOLFINx instead of Dolfin, see: The new DOLFINx solver is now recommended over DOLFIN
You can also pick up various tips on setting appropriate solver options from Default absolute tolerance and relative tolerance - #4 by nate