It manipulates "sketches" which seem to act as a template and search strategy. E.g. for the word algebra problem, the neural net is told to look at the top 4 st

It manipulates "sketches" which seem to act as a template and search strategy. E.g. for the word algebra problem, the neural net is told to look at the top 4 stack elements and figure out how to arrange a pair of arithmetic operations (the sentence is first "parsed" by a RNN.)