2902. Count of Sub-Multisets With Bounded Sum

You are given a 0-indexed array nums of non-negative integers, and two integers l and r. Return the count of sub-multisets within nums where the sum of elements in each subset falls within the inclusive range of [l, r]. Since the answer may be large, return it modulo 109 + 7. A sub-multiset is an unordered collection of elements of the array in which a given value x can occur 0, 1, ..., occ[x]