in reply to Re^2: [OT] The interesting problem of comparing (long) bit-strings.
in thread [OT] The interesting problem of comparing bit-strings.

Making minimal changes to your code to allow it compile here, and it simply never finds anything(very quickly), no matter how simple I make the search criteria:

C:\test\C>cl /W3 bitsearch-oiskuu.c
Microsoft (R) C/C++ Optimizing Compiler Version 15.00.21022.08 for x64
Copyright (C) Microsoft Corporation.  All rights reserved.

bitsearch-oiskuu.c
bitsearch-oiskuu.c(49) : warning C4267: '=' : conversion from 'size_t'
+ to 'U16', possible loss of data
bitsearch-oiskuu.c(78) : warning C4267: '=' : conversion from 'size_t'
+ to 'char', possible loss of data
bitsearch-oiskuu.c(80) : warning C4267: '+=' : conversion from 'size_t
+' to 'char', possible loss of data
Microsoft (R) Incremental Linker Version 9.00.21022.08
Copyright (C) Microsoft Corporation.  All rights reserved.

/out:bitsearch-oiskuu.exe
bitsearch-oiskuu.obj

C:\test\C>bitsearch-oiskuu
Result           -1     Took 1.837746e-004 secs

[download]

I've wasted enough time on it; and won't be expending any more, but here is the modified code that compiles clean (apart from warnings that originate from your posted code):

<Reveal this spoiler or all in this thread>

I'd suggest you enter it in an obfuscated C competition; could be a winner.

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority". I'm with torvalds on this
In the absence of evidence, opinion is indistinguishable from prejudice. Agile (and TDD) debunked

In Section Seekers of Perl Wisdom