[[abstract]]Complex optimisation problems with many degrees of freedom are often characterised by the enormously large configuration space, typically O(eN) or O(N!). The idea of simulated annealing (SA) proposed by Kirkpatrick has been applied to the complex optimisation problems, which can be treated as annealing a statistical mechanical system from high temperature to low temperature; however, the SA is terribly slow for large problem sizes in typically O(N3lnN) time. We discover the hybrid algorithm (HA), which is based on a hybrid mechanism which combines conventional heuristics with low temperature simulated annealing (LTSA), which could be parallelised easily. The HA is a new approach of resolving optimisation problems with O(N) compl...