<s>
In	O
artificial	B-Application
intelligence	I-Application
and	O
operations	O
research	O
,	O
hierarchical	B-Application
constraint	I-Application
satisfaction	I-Application
(	O
HCS	O
)	O
is	O
a	O
method	O
of	O
handling	O
constraint	B-Application
satisfaction	I-Application
problems	O
where	O
the	O
variables	O
have	O
large	O
domains	O
by	O
exploiting	O
their	O
internal	O
structure	O
.	O
</s>
<s>
Thus	O
,	O
if	O
some	O
elements	O
of	O
a	O
set	O
satisfy	O
a	O
constraint	B-Application
,	O
but	O
not	O
all	O
,	O
the	O
subsets	O
of	O
the	O
set	O
are	O
considered	O
.	O
</s>
<s>
In	O
this	O
way	O
,	O
if	O
no	O
elements	O
of	O
a	O
set	O
can	O
satisfy	O
the	O
constraint	B-Application
the	O
whole	O
set	O
can	O
be	O
discarded	O
.	O
</s>
