StrmCkr wrote:Perhaps a bit of nitpicking, but you don't make uniqueness eliminations because the eliminated numbers would leave a multi solution grid, you make them because they would leave a grid that cannot have a unique solution (either 0 or >1 solutions). In all valid puzzles, this means that the eliminated digit would lead to a grid with no solutions.
i read that as saying the same thing twice.
muti solution grids are invalid for any puzzle that must have only one solution.
A unique puzzle can never end up in a multi solution
grid - A multi solution grid is not invalid, it is impossible. Multi solution
subpatterns of the grid are invalid, because they would cause the
grid to have
no solutions. There is a fine difference there.
heres a randomly generated puzzle.
4 at the @ are eliminated using revese bug if i got it right.
No. The basic idea with the Reverse-BUG is that if the already solved cells of two digits form an unavoidable set, then the remaining unsolved cells make up a deadly pattern. In your example, no matter how you fill in the remaining digits 4 and 9, you have solved all digits 4 and 9 in the puzzle. So where is the deadly pattern?
RW