let cc, aa, bb be Int-Location ; for I, J being Program of {INT,(INT *)} st cc <> aa & not I destroys cc & not J destroys cc holds
not if>0 (aa,bb,I,J) destroys cc
let I, J be Program of {INT,(INT *)}; ( cc <> aa & not I destroys cc & not J destroys cc implies not if>0 (aa,bb,I,J) destroys cc )
assume that
A1:
cc <> aa
and
A2:
( not I destroys cc & not J destroys cc )
; not if>0 (aa,bb,I,J) destroys cc
( if>0 (aa,bb,I,J) = (SubFrom (aa,bb)) ';' (if>0 (aa,I,J)) & not if>0 (aa,I,J) destroys cc )
by A2, SCMFSA8B:def 5, SCMFSA8C:121;
hence
not if>0 (aa,bb,I,J) destroys cc
by A1, SCMFSA7B:14, SCMFSA8C:82; verum