maxOr to 0 and iterate over the array to calculate the maximum bitwise OR value of all elements combined.countSubsets that takes the current index, the current bitwise OR value, and a reference to the count of subsets achieving maxOr.maxOr. If it is, increment the count.countSubsets recursively twice: once including the current element (updating the current OR value) and once excluding it (keeping the current OR value unchanged).countSubsets starting from index 0 and an initial OR value of 0.maxOr.