integer function rescode(iseq,nam,itype)
      implicit real*8 (a-h,o-z)
      include 'DIMENSIONS'
      include 'COMMON.NAMES'
      include 'COMMON.IOUNITS'
      character*3 nam,ucase

      if (itype.eq.0) then

      do i=1,ntyp1
        if (ucase(nam).eq.restyp(i)) then
          rescode=i
          return
        endif
      enddo

      else

      do i=1,ntyp1
        if (nam(1:1).eq.onelet(i)) then
          rescode=i
          return  
        endif  
      enddo

      endif

      write (iout,10) iseq,nam
      stop
   10 format ('**** Error - residue',i4,' has an unresolved name ',a3)
      end