anchor.diff:        
         ASSERT (low > 0)
         j = ishft(low-1,-bit_kind_shift)+1   ! Find integer in array(Nint)
  -      n = iand(low,bit_kind_size-1)        ! mod(low,bit_kind_size)
  +      n = iand(low-1,bit_kind_size-1)+1      ! mod(low,bit_kind_size)
         ASSERT (high > 0)
         k = ishft(high-1,-bit_kind_shift)+1
  -      m = iand(high,bit_kind_size-1)
  +      m = iand(high-1,bit_kind_size-1)+1
         if (j==k) then
           nperm = popcnt(iand(det1(j,ispin),                           &
               iand(ibset(0_bit_kind,m-1)-1_bit_kind,ibclr(-1_bit_kind,n)+1_bit_kind)))
         else
  -        nperm = nperm + popcnt(iand(det1(k,ispin),ibset(0_bit_kind,m-1)-1_bit_kind)) +&
  +        nperm = nperm + &
  +            popcnt(iand(det1(k,ispin),ibset(0_bit_kind,m-1)-1_bit_kind)) +&
               popcnt(iand(det1(j,ispin),ibclr(-1_bit_kind,n)+1_bit_kind))
           do i=j+1,k-1
             nperm = nperm + popcnt(det1(i,ispin))
  
positive.code:         
          ASSERT (low > 0)
          j = ishft(low-1,-bit_kind_shift)+1   ! Find integer in array(Nint)
          n = iand(low,bit_kind_size-1)        ! mod(low,bit_kind_size)
          ASSERT (high > 0)
          k = ishft(high-1,-bit_kind_shift)+1
          m = iand(high,bit_kind_size-1)
          
          if (j==k) then
            nperm = nperm + popcnt(iand(det1(j,ispin),                 &
  
negative.code:           
            ASSERT (low > 0)
            j = ishft(low-1,-bit_kind_shift)+1   ! Find integer in array(Nint)
            n = iand(low-1,bit_kind_size-1)+1        ! mod(low,bit_kind_size)
            ASSERT (high > 0)
            k = ishft(high-1,-bit_kind_shift)+1
            m = iand(high-1,bit_kind_size-1)+1
            
            if (j==k) then
              nperm = nperm + popcnt(iand(det1(j,ispin),               &
  