The final option concerns specifying two lines in the line editor's array, then searching for a rule which will lead from the first line to the second. Again, certain transitions may be forced by previously inserting them in the rule table and marking them.
When a rule complying with the requirements is found, the program pauses, awaiting a decision to accept the result, or to continue searching for another, if any. If, at any stage, no rule can be found, the program announces this fact when it pauses.