Write a method that returns 'true' if it is possible to obtain the 'target' sum by selecting any number of elements from the array 'nums'. If it is not possible, return 'false'. There may be more than one way to obtain the sum, but that doesn't matter. You just need to return 'true' if it is possible and 'false' if it is not. This problem is easily solved using backtrack recursion, but that is NOT required. The array 'nums' will be short enough that you should not have problems with timing out unless you have horrible efficiency.