anchor.diff:                  ! processor.
                   do iattempt = 1, nparticles(1)
   
  -                    ! TODO: initiator.
                       call select_cluster(nparticles(1), D0_pos, max_cluster_size, cdet, cluster)
   
                       if (cluster%excitation_level <= truncation_level+2) then
  
positive.code:         use ccmc_data, only: cluster_t
          use excitations, only: get_excitation_level
          use dSFMT_interface, only: genrand_real2
          use fciqmc_data, only: f0, tot_walkers, walker_population, walker_dets
          use proc_pointers, only: decoder_ptr
          use utils, only: factorial
  
  
negative.code:                         call spawner_ccmc(cdet, cluster, nspawned, connection)
  
                          if (nspawned /= 0) then
                              call create_spawned_particle_ptr(cdet, connection, nspawned, spawned_pop)
                          end if
  
                          ! Does the cluster collapsed onto D0 produce
  