public static NFA Union(NFA m1, NFA m2)
{
var ret = new NFA(m1);
m1.MakeSingleEndState();
var ret2 = new NFA(m2);
m1.MakeSingleEndState();
// Renames elements before combining them
var newNames = Enumerable.Range(0, ret.States.Count + ret2.States.Count)
.Select(s => $"q{s}");
ret.Rename(newNames.Take(ret.States.Count).ToArray());
ret2.Rename(newNames.Skip(ret.States.Count).Take(ret2.States.Count).ToArray());
// Combines the tow states
ret.States = ret.States.Concat(ret2.States).ToDictionary(s => s.Key, s => s.Value);
// Sets new start state
ret.StartState.IsStartState = false;
ret2.StartState.IsStartState = false;
var startState = new NFAState(ret.GetUniqueName(), false, true);
startState.Transitions['λ'] = new List <NFAState> {
ret.StartState, ret2.StartState
};
ret.StartState = startState;
ret.States.Add(startState.Name, startState);
ret.SetFinalStates();
ret.MakeSingleEndState();
ret.Rename();
return(ret);
}