Making accept method faster

[ivanDonadello]

The accept method for accepting a string could be made faster by stopping the iteration over the string symbols when the DFA is in a sink state. Here is my custom solution that should work:

    ...
    current_states = reduce(set.union, map(lambda x: dfa.get_successors(x, temp), current_states),set(),)

    sink_state = all(is_sink(dfa, state) for state in current_states)
    if sink_state:
        break
is_accepted = any(dfa.is_accepting(state) for state in current_states)

where

def is_sink(dfa: SymbolicDFA, current_state: int):
    sink = True
    for output_state in dfa._transition_function[current_state].keys():
        if output_state != current_state:
            sink = False
    return sink

Hope it will be useful. My 2 cents.

Ivan