Rust: Sorted Keys In BTreeMap

BTreeMap in rust&rsquo;s equivalent of C++&rsquo;s std::map , the former representing a self balancing tree data structure while the latter uses self-balancing binary search tree implementation (in the form of red-black tree). &#xA;&#xA; Ordering Limitation &#xA;&#xA; BTreeMap only supports ascending order by default and does not provide a built-in descending order, unlike C++. &#xA;&#xA;…