NFA to DFA Exercise Help

First you see "Choose a state to expand": Just click one of the nodes in the box on the right.

That opens a box that says "Expand on what terminal?" There you type in one of the letters (terminals) in the alphabet. That would be a or b.

Once you type the letter and click "OK", then you can do one of two things: You can click a spot in the box on the right where you want the node. Or you can click on an existing node if you want the transition to go to that. But if you click on an empty spot to create a new node, you next get asked: "Which group of NFA states will that go to on ?" So, you just type the state names, separated by commas. So, for example, you could type "q0, q1". That will place a node with that label. Note that if you type a list of states that already has a node, it will tell you that it already exists. In which case, just do it over again, clicking on the node this time as the target of the transition.

If your node list is not correct (the exercise knows what the target node list ought to be for this transition), then it will tell you "State Label is incorrect". In which case, you need to figure out why your list was wrong, and then try again.

At the end, if you think you did all the expansions, just hit "Grade".

This exercise is very forgiving. So long as you eventually reach the correct end it it is supposed to give you credit, no matter how many mistakes you make on the way.