anchor.diff:  
     END SUBROUTINE Print_Quad
   
  +  SUBROUTINE NewQuNode(qA,count)
  +    INTEGER :: count
  +    TYPE(QuTree), POINTER :: qA
  +    ALLOCATE(qA);  count=count+1
  +    qA%Num=count
  +    qA%Norm=Zero
  +    NULLIFY(qA%Quad00)
  +    NULLIFY(qA%Quad01)
  +    NULLIFY(qA%Quad10)
  +    NULLIFY(qA%Quad11)
  +  END SUBROUTINE NewQuNode
  +
  +
     FUNCTION SpAMM(qA,qB,tolerance) RESULT(qC)
       IMPLICIT NONE
       TYPE(QuTree), POINTER                :: qA,qB
  
positive.code: !!$      GlblQT%Hash=Hash+4*Shift
  !!$      Hash11=GlblQT%Hash
  !
  
negative.code:     LOGICAL :: do00x00,do01x10,do10x00,do11x10, &
                 do00x01,do01x11,do10x01,do11x11
      ! Bounds
      qC%Box(1,1)=qA%Box(2,1)
      qC%Box(1,2)=qA%Box(2,2)
      qC%Box(2,1)=qB%Box(1,1)
      qC%Box(2,2)=qB%Box(1,2)
      ! Blocks
      IF(qA%Siz==BLOCK_SIZE)THEN
         IF(.NOT.ALLOCATED(qC%Blok))THEN
  