3. This problem is concerned with the range queries on a binary search tree T whose keys are real numbers. Let h denote the height of T. The range query is a generalization of the normal search operation. The range of a range query on T is defined by a pair [x,x], where x and xr are real numbers and xi S xr. Note that xi and xr need not be the keys stored in T. (20 points) You are asked to design an algorithm to perform the following range queries on T. That is, given a range [xixr], design an O(h + k) time algorithm for the range-report(x, xr) operation on T: reporting all keys x in T such that x SxSxr, where k is the number of keys of T in the range [XI, Xr] (i.e., k is the size of the output of the query, and thus this is also an output-sensitive algorithm). Further, it is required that all keys in the range [x,xr] be reported in a sorted order