anchor.diff:  !    do c=c_start,c_end
   !      do b=b_start,d
   !        do a=a_start,min(b,c)
  -          if (dabs(U(a,b,c)) < 1.d-15) then
  +          if (dabs(U(a,c,b)) < 1.d-15) then
               cycle
             endif
             idx = idx+1_8
             call bielec_integrals_index(a,b,c,d,key(idx))
  -          value(idx) = U(a,b,c)
  +          value(idx) = U(a,c,b)
           enddo
         enddo
       enddo
  
positive.code:     call map_unique(map_c)
  
    enddo
  
  end
  
negative.code:   ASSERT (LDB >= k_max)
    ASSERT (LDB >= l_max)
  
    allocate( key(i_max*j_max*k_max), value(i_max*j_max*k_max) )
    allocate( U(a_start:a_end, b_start:b_end, c_start:c_end) )
  
    do d=d_start,d_end
      U = 0.d0
  