anchor.diff:    !$OMP PARALLEL NUM_THREADS(procs) default(shared)
     iter = 0
     time = 0.0_WP
  +  write_sum = 0.0_WP
     do while (time .lt. tfin)
       !$OMP MASTER
       iter = iter + 1
  
positive.code:   use posvel
    use neighbors
    use forces
    implicit none
    character(30) :: init_file, proc_string
    integer :: i, unit
  
negative.code:                 cbinz = binz + stz
                  do j = 1, part_count(cbinx,cbiny, cbinz)
                    nb = binpart(j,cbinx,cbiny,cbinz)
                    if(nb .le. p) cycle
                    distx = px(p) - px(nb)
                    disty = py(p) - py(nb)
                    distz = pz(p) - pz(nb)
  