For a 5×4 Minesweeper grid (X=5, Y=4), build a DataFrame with columns 'x' and 'y' containing every coordinate, ordered (0,0), (0,1), (0,2), (0,3), (1,0), ….
'x'
'y'
(0,0), (0,1), (0,2), (0,3), (1,0), …
solve(...)