MEX Spectrum

You are given an array $A$ of length $N$ consisting of non-negative integers, where $0 \leq A_i \leq N$ for every $i$. In one **operation**, you may: - Choose any subarray $A[l \ldots r]$ (a contiguous segment with $1 \leq l \leq r \leq N$). - Compute $m = \mathrm{MEX}(A_l, A_{l+1}, \ldots, A_r)$. - Choose any index $i$ with $l \leq i \leq r$, and set $A_i := m$. For **every** integer $K$ from $