subroutine distwork(myid,numprocs,nmax,mystart,myend,my_veclen)
!     There are numprocs of MPI processes calling this routine
!     Distribute different sections to the processes
      implicit none

!     Input variables
      integer :: myid,nmax,numprocs
!     Output variables
      integer :: mystart,myend
!     Local variables
      integer :: rest, my_veclen

      rest = mod(nmax,numprocs)
!      if(rest.gt.numprocs/2) then
      if(rest .ne. 0) then 
        ! If each process takes my_veclen, total will be bigger than nmax
        my_veclen = (nmax+(numprocs-rest))/numprocs
        mystart = 1 + myid*my_veclen
        myend = mystart + my_veclen - 1
        if(myid.eq.numprocs-1) myend = nmax
      else
        ! If each process takes my_veclen, total will be less than nmax
        my_veclen = nmax/numprocs
        mystart = 1 + myid*my_veclen
        myend = mystart + my_veclen - 1
        if(myid.eq.numprocs-1) myend = nmax
      endif
      end subroutine distwork