Hermione is training the Liquefacio spell which allows her to liquefy objects and living creatures. She is already quite good at liquefying books, plants, and rats, so she decided to go one step further and try to do it with her cat Crookshanks. Of course she wants Crookshanks to get back her original shape and so it is important that she does not lose one single drop of the liquid she will transform Crookshanks into.
Illustration of the first sample. The first two kettles are large enough for the cat. Since the second has less volume than the first, it is the only solution. She therefore decided to put Crookshanks in a kettle before performing the spell, and, to stay inconspicuous, she wants the kettle to be as small in volume as possible. She asked Dobby to help her find a suitable kettle. He showed her a large selection of cylindrical kettles from the Hogwarts kitchen, and now she has to decide which one she wants to take.
The input consists of:
Output the number of the smallest kettle which is large enough for Crookshanks. If there are several optimal solutions you can output any of them. If there is no such kettle, output impossible.
3 19 2 3 4 2 6 1
2
2 199 1 2 2 3
impossible
3 100 2 4 8 2 32 1
3