<s>
Connectionist	B-Algorithm
temporal	I-Algorithm
classification	I-Algorithm
(	O
CTC	O
)	O
is	O
a	O
type	O
of	O
neural	O
network	O
output	O
and	O
associated	O
scoring	O
function	O
,	O
for	O
training	O
recurrent	B-Algorithm
neural	I-Algorithm
networks	I-Algorithm
(	O
RNNs	O
)	O
such	O
as	O
LSTM	B-Algorithm
networks	O
to	O
tackle	O
sequence	O
problems	O
where	O
the	O
timing	O
is	O
variable	O
.	O
</s>
<s>
It	O
can	O
be	O
used	O
for	O
tasks	O
like	O
on-line	O
handwriting	B-Application
recognition	I-Application
or	O
recognizing	O
phonemes	O
in	O
speech	O
audio	O
.	O
</s>
<s>
softmax	B-Algorithm
)	O
,	O
which	O
is	O
fitted	O
through	O
training	O
to	O
model	O
the	O
probability	O
of	O
a	O
label	O
.	O
</s>
<s>
Equivalent	O
label	O
sequences	O
can	O
occur	O
in	O
many	O
ways	O
–	O
which	O
makes	O
scoring	O
a	O
non-trivial	O
task	O
,	O
but	O
there	O
is	O
an	O
efficient	O
forward	B-Algorithm
–	I-Algorithm
backward	I-Algorithm
algorithm	I-Algorithm
for	O
that	O
.	O
</s>
