Fixed bug with last state detection

main.go

@@ -128,6 +128,9 @@ func thompson(re string) State {
 			for i := range s1.output {
 				s1.output[i].transitions[s1.content] = &s1
 			}
+			// Reset output to s1 (in case s1 was a union operator state, which has multiple outputs)
+			s1.output = nil
+			s1.output = append(s1.output, &s1)
 			nfa = append(nfa, s1)
 		case '|':
 			s1 := pop(&nfa)

nfa.go

@@ -21,6 +21,10 @@ func verifyLastStatesHelper(state *State, visited map[*State]bool) {
 		state.isLast = true
 		return
 	}
+	if state.transitions[state.content] == state { // Eg. a*
+		state.isLast = true
+		return
+	}
 	if visited[state] == true {
 		return
 	}