Avoid The Landmines

You are given an integer array $A$ of size $N$ and a positive integer $M$. This array contains a hidden message which can be decoded by the following algorithm: ``` int ox[N+1], oy[N+1]; for(int i = 1; i ≤ N; i++) { ox[i] = A[i] / M; oy[i] = A[i] % M; } ``` There are $N$ landmines on the xy-plane, such that the $i^{th}$ landmine $(1\le i \le N)$ is located at $(ox_i,oy_i)$. Initially,