In computer science, a pebble automaton is an extension of tree walking automata which allows the automaton to use a finite amount of "pebbles", used for marking tree node. The result is a model stronger than ordinary tree walking automata, but still strictly weaker than branching automata.
Famous quotes containing the word pebble:
“I seem to have been only like a boy playing on the seashore, and diverting myself in now and then finding a smoother pebble or a prettier shell than ordinary, whilst the great ocean of truth lay all undiscovered before me.”
—Isaac Newton (16421727)