G - Maxpool

Robert is a maths teacher and he made a question for his students. Question is a matrix of $N$ X $N$ with all distinct elements from $1$ to $N*N$. One has to apply **maxpool** function of filter matrix $2$ X $2$ to get the answer, that is for each $2$ X $2$ matrix you have to write the maximum element in corresponding matrix of size $(N-1)$ X $(N-1)$. for example if $N$ = $3$ and matrix given is