<s>
In	O
computational	O
complexity	O
theory	O
,	O
a	O
leaf	B-General_Concept
language	I-General_Concept
is	O
a	O
method	O
of	O
characterizing	O
a	O
complexity	O
class	O
by	O
formalizing	O
what	O
it	O
means	O
for	O
a	O
machine	O
to	O
"	O
accept	O
"	O
an	O
input	O
.	O
</s>
