//Gives the first border that can be placed on the given cell
border_names first_border(const board & board, const point & idx)
{
//Return the first free border
auto bb = board.borders(idx);
for (int i = borders_first; i < borders_count; ++i)
if (!bb[i]) return (border_names)i;
//No such border
return none;
}
//Gives the first border that can close the given cell
border_names closing_border(const board & board, const point & idx)
{
//Setup
auto bb = board.borders(idx);
border_names result = none;
int closed_cnt = 0;
//Count closed borders and find free borders
for (int i = borders_first; i < borders_count; ++i)
if (bb[i]) ++closed_cnt;
else result = (border_names)i;
//There must be 3 closed borders
if (closed_cnt != 3)
return none;
return result;
}
//Get borders count
int border_count(const board & board, const point & idx)
{
return border_count(board.borders(idx));
}