No 4 Please

An array $B$ of length $M$ is said to be *good* if no two elements from different indices sum to $4$. That is, $B$ is *good* if for every pair $(i, j)$ satisfying $1 \le i \lt j \le M$, we have $(B_i + B_j) \ne 4$. --- You are given an array $A$ of length $N$ such that $1 \le A_i \le 3$ for each index $i$. You would like to make $A$ a *good* array. To achieve this, you can repeatedly ch