print(chord)

				if c == '' then
					Problem.data[y][x] = d
				elseif c < 2 then  -- not overfull
					Problem.data[y][x] = Problem.data[y][x]*10 + d

				if c == '' then c = 0 end
				if c < 2 then  -- not overfull
					Problem.data[y][x] = c*10 + d
				end
			end
		end
	elseif chord == 'backspace' then
		-- cursor visible
		local x,y = Cursor[1], Cursor[2]
		if x > 0 and y > 0 then
			-- it's not in the provided square
			if x ~= Problem.x or y ~= Problem.y then
				local c = Problem.data[y][x]
				if c ~= '' and c > 0 then
					Problem.data[y][x] = math.floor(c/10)