4 ms·
> (if I put a 3 here then it reaches here and here by knight’s move therefore it can’t go here) A possibly-simpler way to look at it is the inverse. Putting a
by ghusbands 6y ago
> (if I put a 3 here then it reaches here and here by knight’s move therefore it can’t go here)
A possibly-simpler way to look at it is the inverse. Putting a 3 here or here (where it must go) both block this other place, so we know this other place is blocked either way.
- dan-robertson 6y agoYes, that’s something I tried thinking about but computing the intersection of two or more quite large regions turns out to be harder than using the symmetry to only look at one region. There are also tricks one can learn for eg dominos.