Kleene's Algorithm

Kleene's algorithm converts a nondeterministic finite automaton into an equivalent regular expression, establishing the equivalence between automata and regular expressions as two ways of describing the same regular languages. It is named for Stephen C. Kleene and traces to his 1956 paper, with equivalent methods later given by Brzozowski and McCluskey and by McNaughton and Yamada. The algorithm works by incrementally building, for each pair of states, a regular expression describing the paths between them that pass only through lower-numbered intermediate states, then combining the expressions from the start state to every accepting state into the automaton's overall regular expression. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/