Near Yet Far

*This is the easy version of the problem. You only need to compute the score for the given array.* You are given an array $A$ of length $N$, as well as an integer $K$ ($2 \le K \le N$). A sequence of indices $(i_1, i_2, \ldots, i_r)$ is said to be *valid* if: - $i_1 \lt i_2 \lt \ldots \lt i_r$ - That is, the indices are viewed in increasing order. - $i_j + 1 \ne i_{j+1}$ for every $1 \le j