Given an array of distinct integers nums and a target integer target, return the number of possible combinations that add up to target.
The test cases are generated so that the answer can fit in a 32-bit integer.
Note: Different sequences are counted as different combinations. For example, (1, 1, 2) and (1, 2, 1) and (2, 1, 1) are all counted separately.
1 <= nums.length <= 2001 <= nums[i] <= 1000nums are unique1 <= target <= 1000nums = [1,2,3], target = 47nums = [9], target = 30