The subset sum problem is an important problem of computer science. It can be stated as follows: Given a set of integers, does any subset of them sum to zero? For example, given the set { -7, -3, -2, 5, 8}, the answer is "yes" because the subset { -3, -2, 5} sums to zero. The problem is NP-Complete. It can be reformulated to the 3SAT. 