A P system for Hamiltonian cycle problem

P system is a new kind of distributed parallel computing model. In the P system, objects in each membrane can follow the evolution of the maximum parallelism principle, so we can solve NP-hard problem in polynomial time. In this paper, we design a family of P system with to judge whether there is a Hamiltonian cycle and find all Hamiltonian cycle in an undirected graph, and then an instance is given to illustrate the feasibility and effectiveness of our designed P systems.