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Can/do you write in C? Would someone care to translate this? I'll do it tomorrow at work, but if someone can post and/or email me an equivalent C version it w

Can/do you write in C? Would someone care to translate this? I'll do it tomorrow at work, but if someone can post and/or email me an equivalent C version it will reduce my time. Not a problem, but just more convenient. You'll need to give me some way to contact you so I can send you the results. EDIT: I've just realised the spec I usually give asks for the first occurence of a key to be returned in the case where there are duplicate keys. I'll modify my tests to account for that. It's an especially useful feature in a binary search, but rarely implemented.

Dove 17y ago
Having to do it in C is even more perverse than doing it in my head. ;)
- Dove 17y ago
  In all seriousness, if you have to translate it, don't bother. I write in C nearly daily, and I certainly wouldn't trust myself not to lose something in translation. I'd be interested in what's in your test suite, though. I must sheepishly admit that my 'fairly exhaustive' test consisted of running the above random input until I'd seen all the usual tricky cases go by: - an array of length zero - an array of length one - an array of length two - the value is present - the value is absent and too small - the value is absent and too large - the value is absent and in the middle - the value is the first entry - the value is the last entry - the array is all one value - there are multiple copies of the value you're looking for If you've got anything more interesting in that test suite, that'd be good to know. Like I said, I represent the one-bazillionth of programmers that actually have a recurring professional interest in correctly coding binary searches.
  - joezydeco 17y ago
    An array of length Maxint?
    - ableal 17y ago
      Good call. As per link in http://news.ycombinator.com/item?id=1277701 http://news.ycombinator.com/item?id=1277701 (elsewhere in this page): the binary search program that Bentley proved correct and subsequently tested in Chapter 5 of Programming Pearls contains a bug [...] it fails if the sum of low and high is greater than the maximum positive int
  - ay 17y ago
    "the array is all one value" got me. After fixing that, despite of the excessive verbosity, my experiment in literate programming passes the other tests - but I'm sure I coded a few more bugs in it - if you have some stock suite to get it through - would be very interested to know how many! http://stdio.be/mybsearch/mybsearch.txt http://stdio.be/mybsearch/mybsearch.txt for the text and the http://stdio.be/mybsearch/mybsearch.c http://stdio.be/mybsearch/mybsearch.c for the notangle-d C code, if you fancy to look at it.

Dove 17y ago

Having to do it in C is even more perverse than doing it in my head. ;)

Dove 17y ago
In all seriousness, if you have to translate it, don't bother. I write in C nearly daily, and I certainly wouldn't trust myself not to lose something in translation. I'd be interested in what's in your test suite, though. I must sheepishly admit that my 'fairly exhaustive' test consisted of running the above random input until I'd seen all the usual tricky cases go by: - an array of length zero - an array of length one - an array of length two - the value is present - the value is absent and too small - the value is absent and too large - the value is absent and in the middle - the value is the first entry - the value is the last entry - the array is all one value - there are multiple copies of the value you're looking for If you've got anything more interesting in that test suite, that'd be good to know. Like I said, I represent the one-bazillionth of programmers that actually have a recurring professional interest in correctly coding binary searches.
- joezydeco 17y ago
  An array of length Maxint?
  - ableal 17y ago
    Good call. As per link in http://news.ycombinator.com/item?id=1277701 http://news.ycombinator.com/item?id=1277701 (elsewhere in this page): the binary search program that Bentley proved correct and subsequently tested in Chapter 5 of Programming Pearls contains a bug [...] it fails if the sum of low and high is greater than the maximum positive int
- ay 17y ago
  "the array is all one value" got me. After fixing that, despite of the excessive verbosity, my experiment in literate programming passes the other tests - but I'm sure I coded a few more bugs in it - if you have some stock suite to get it through - would be very interested to know how many! http://stdio.be/mybsearch/mybsearch.txt http://stdio.be/mybsearch/mybsearch.txt for the text and the http://stdio.be/mybsearch/mybsearch.c http://stdio.be/mybsearch/mybsearch.c for the notangle-d C code, if you fancy to look at it.