Re: How does a computer solve crosswords?
OK - the light has gone on for both of them! Thanks.
The first one is clever. Though I don't feel too upset I didn't get it - I think that an anagram on "Johnny rents" (or "a flat in Paris) could easily be indicated by the "out", and the fact that both "Johnny rents" and "a flat in paris" have twelve letters led me seriously astray.
The second one I really should have got. I admit I cheated - I typed the clue into Google and found "Train, or part of one (5)" - and that's basically the same clue.
Thanks very much for your help. Just confirms to me that I'm not really a crossword person. I'll stick to Sudoku - I'm good at those!