def literal(literal: Literal):
nfa = NFA(Alphabet({Automata.EPSILON}))
start = nfa.addState()
final = nfa.addState()
nfa.start = {start}
nfa.final = {final}
for label in literal.alphabet:
for start in nfa.start:
for final in nfa.final:
nfa.addTransition(start, final, label)
return nfa
def star(nfa: NFA):
new_start = nfa.addState()
new_end = nfa.addState()
for start in nfa.start:
nfa.addTransition(new_start, start, NFA.EPSILON)
for final in nfa.final:
nfa.addTransition(final, new_end, NFA.EPSILON)
for start in nfa.start:
for final in nfa.final:
nfa.addTransition(final, start, NFA.EPSILON)
nfa.addTransition(new_start, new_end, NFA.EPSILON)
nfa.start = [new_start]
nfa.final = [new_end]
return nfa
def union(nfa1: NFA, nfa2: NFA):
nfa = NFA(Alphabet({Automata.EPSILON}))
equiv_states = {}
for state in nfa1.states:
equiv_states[state] = nfa.addState()
for state in nfa2.states:
equiv_states[state] = nfa.addState()
for state in nfa1.states:
for label in nfa1.alphabet:
for dest in nfa1.transitions[state][label]:
nfa.addTransition(equiv_states[state], equiv_states[dest], label)
for state in nfa2.states:
for label in nfa2.alphabet:
for dest in nfa2.transitions[state][label]:
nfa.addTransition(equiv_states[state], equiv_states[dest], label)
new_start = nfa.addState()
new_end = nfa.addState()
for start in nfa1.start:
nfa.addTransition(new_start, equiv_states[start], NFA.EPSILON)
for start in nfa2.start:
nfa.addTransition(new_start, equiv_states[start], NFA.EPSILON)
for final in nfa1.final:
nfa.addTransition(equiv_states[final], new_end, NFA.EPSILON)
for final in nfa2.final:
nfa.addTransition(equiv_states[final], new_end, NFA.EPSILON)
nfa.start = {new_start}
nfa.final = {new_end}
return nfa
def emptyWord():
nfa = NFA(Alphabet())
nfa.start = {nfa.addState()}
nfa.final = nfa.start.copy()
return nfa