Here is the best game ever, Dancing Floor Machine. This machine is brilliant! Every grid is like a switch on/off button, whenever you push on a grid on the floor, that grid and the neighbor grids turn on or off depending on the current condition. If it is off, it will turn on, otherwise turn off. For example:
At the beginning of the given example, $3$ is already on, the rest is off, When I push on $5$, $5$ turns on, and the neigbor grids as well, $2$,$4$,$6$ and $8$.
The question is
$1-$ At least how many times do we need to press on the button on the floor shown as below to turn them all on?
$2-$ Since you learn the methodology while solving previous question, at most how many times do you need to press on the buttons to turn them all on in the worst case scenario?
Good Luck!