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For the lowercase English letter $\alpha$, let $\text{ord}(\alpha)$ denote the *order* of $\alpha$ in the alphabet, under the standard ordering $a, b, c, \ldots, z$. For example, $\text{ord}(b) = 2, \text{ord}(j) = 10,$ and $\text{ord}(z) = 26$. You are given a string $S$ containing $N$ lowercase English letters. You can perform the following $2$ operations on it: 1. Choose a [subsequence](