We know that the subset sum problem is NP-Complete. Remember that the subset sum problem begins with an array of positive integers A and a targeted sum k. It then asks whether there exists a subset of A that sums up to this target value k. We would like to show that the following problem called Zero sum is also NP-Complete. Given a set of integers, is there a non-empty subset whose sum is zero.
Show that the zero sum problem is in NP-Complete.