Ayende @ Rahien

My name is Oren Eini
Founder of Hibernating Rhinos LTD and RavenDB.
You can reach me by phone or email:


+972 52-548-6969

, @ Q c

Posts: 6,026 | Comments: 44,842

filter by tags archive



Ha ha, it's quite subtle, but so obvious once you spot it.


I think there is something 'else' missing ;-)


LOL, I didn't saw it either

Marc Brooks

Not to mention the sheer lunacy of mid not being related to target in any discernable way. Ugh.

(oh, yeah, and missing else)


Apart from missing else, what about arithmetic overflow?

I would change the line: var mid = (left + right + 1) / 2;

to this: var mid = left + (right - left + 1) / 2;

You still get the same result, but it's a little bit safer for higher values.


The bug aside, I'd use checked((left + right + 1) / 2).

Roman Boiko

Another potential problem: behavior of comparator might be not aligned with subtraction, so that

_comparator.Compare(mid-1, mid) >=0


This is really a tricky problem to spot. :) Everyone is focused on the code inside the brackets and the missing "else" is not being observed very fast.

Adam Fridental

Sorry to dissapoint, took me a second.

Anyway, I don't belive in scoping braces when they contain 1 line, it's not safer and not easier to read.. just redundant.

Comment preview

Comments have been closed on this topic.


No future posts left, oh my!


  1. Technical observations from my wife (3):
    13 Nov 2015 - Production issues
  2. Production postmortem (13):
    13 Nov 2015 - The case of the “it is slow on that machine (only)”
  3. Speaking (5):
    09 Nov 2015 - Community talk in Kiev, Ukraine–What does it take to be a good developer
  4. Find the bug (5):
    11 Sep 2015 - The concurrent memory buster
  5. Buffer allocation strategies (3):
    09 Sep 2015 - Bad usage patterns
View all series


Main feed Feed Stats
Comments feed   Comments Feed Stats