This is a good game.
When you use sub a or b (in main) at the end of the last location list, it crashes. And the same if we put a sub a in main then sub b at the end of the list sub a.
The robot image remains on top of the display when you choose an instruction. It would be interesting to create a table of levels in order to better visualize them (or to choose them independently) and to have a kind of reward which would indicate that we did complete well. A little sounds would not be refuse.
In the console, since it stops too quickly.
I found a trick to see the error concerning sub a and b. By clicking first in the console then by pressing delete and quickly pressing the print screen. XD, here is the message:
terminate called after throwing an instance of 'std::out_of_range'
what(): vector:: _ M_range_check: __n (which is 10) >= this-> size() (which is 10)