Contact Form Submission - Mistake (Advanced - Sum over Subsets DP)

[maggieliu05]

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URL: https://usaco.guide/adv/dp-sos
Module: Advanced - Sum over Subsets DP
Topic: Mistake
Message:
The following explanation:
Notice how in both of these examples we don't seem to be saving much information between different subsets which is the essence of DP.
Define
$\texttt{SOS}(\texttt{mask}, x)$
to be the sum of subsets of mask such that the first
$x$
bits of the subset are identical to the first
$x$
bits of mask.
For example,
$\texttt{SOS}(1001001, 3)$
includes the subsets
$1001001$
,
$1000001$
,
$1001000$
,
$1000000$
which all have the same common prefix of
$100$
.

I'm pretty sure It should be the last x bits, since if it were the first x bits, then when you transition to x+1 the answer is non-increasing which makes no sense

[bqi343]

it should be something like last $n-x$ bits