Kruijswijk's resolver: work each order out from the others, and when that
turns out to be circular -- which it genuinely can be, this game has real
paradoxes in it -- guess, check whether both guesses agree, and fall back to
a stated rule when they do not. A ring of units all moving into each other
all move. A convoy paradox is settled by Szykman's rule, which is a
convention rather than a deduction and is written down as one.
Four strengths do the work: attack, hold, defend and prevent. A move has to
beat the right one of them strictly, so an unsupported attack never takes a
supported province and a tie is always a bounce.
Worth noting what falls out rather than being written down. A unit cannot
drive out a countryman, so a move against one has attack strength zero, so it
cuts no support -- which is why a power cannot cut its own support. That is a
consequence of Calhamer's rule, not a separate one, and the comment says so
where the zero is returned.
Twenty-one cases, all written out in full so a reader can check them by hand.
A game of this ends in a solo, an elimination, a draw, or somebody else's
solo, and none of those is a win or a loss in the shape the other games on
this site use. The draw is the one that matters: it is the usual outcome and
it is neither, so it cannot borrow either tune.
Convoy routing is breadth-first over the fleets actually ordered to convoy
this army, so it returns the shortest chain and answers null rather than
guessing. It takes a set of fleets to treat as already gone, which is what
the adjudicator will need to ask whether a convoy survives being attacked.
The tests found a wrong assumption of mine rather than a wrong line of code:
taking the Channel out of a London to Brest convoy leaves no route at all.
The North Sea does not touch the Mid-Atlantic on this board -- the long way
round is over the top through the Norwegian Sea -- so the Channel is the
whole western sea route.
Seventy-five provinces as two graphs, because an army and a fleet do not move
on the same one, and three provinces whose two coasts do not connect.
The topology is a fact about a published game and free to use; the artwork is
not, and there is none here -- the map will be generated from this data the
way the cave game's dodecahedron is. The name is a working one for the same
reason the starship game is not called what you expect.
The tests check the board against itself, and symmetry is the one that pays:
it found the Skagerrak wired to the Baltic, which would have opened a back
door into the Baltic and made Denmark worth nothing.
jcoffey-dev