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...you spend 15 minutes trying everything to get the debugger to break on a statement only to realise that you've built in Release mode.
cheers
Chris Maunder
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Yeah is this fun or what.
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OK, here you go:
break;
What do you get when you cross a joke with a rhetorical question?
The metaphorical solid rear-end expulsions have impacted the metaphorical motorized bladed rotating air movement mechanism.
Do questions with multiple question marks annoy you???
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You've already got a kit-kat?
"When I was 5 years old, my mother always told me that happiness was the key to life. When I went to school, they asked me what I wanted to be when I grew up. I wrote down 'happy'. They told me I didn't understand the assignment, and I told them they didn't understand life." - John Lennon
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When you say "try everything", what dI'd you try?
Try Grapple for Android, it has a naked pixel guy in it!
Also, loads of blood and some snakes.
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 At least you realized this after 15 minutes and not like, 2 hours. 
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It happens, regardless how clever you are, how informed you are.
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Yeah, it's lack of breaks, nothing to do with getting old 
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Debugging release versions is no problem, provided you decide up front that you want that ability and build it in. Eh.
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I once spent an entire morning on that... 
On the plus side I did get my break as it was lunch time when I figured it out
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My understanding is that obviously the divide & conquer sorting algorithms of O( n log n ) are far better than the ones of O( n^2 ), except for the case of a small size of data, in which insertion sort is used, as even it is is better than bubble sort.
But it was my experience learning BASIC and then later FORTRAN that bubble sort was introduced as a "read & type in" algorithm. (It was only later when I studied C that I learned about these far better sort algorithms.) So I wonder why is bubble sort even taught? The only explanation I can come up with is that is only a few lines long, with a double for loop (i.e., a very elementary CS concept), so it is easy to "plug & chug" into a program that requires it, without going into the theory of sorting algorithms - and as well would have been useful in the days of the small-byte program, when every line of code was valuable.
Is there some use of this that I am missing here? I suppose that back in the quaint days of "book distribution" (i.e., the only inexpensive way to transfer program code was to put it in a book and have the user type it in, LOL), using bubble sort saved on tedious typing as well.
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No!!! For data size less than 16, a bubble sort is faster. Much less setup overhead. Do the math!
Gus Gustafson
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gggustafson wrote: For data size less than 16, a bubble sort is faster. Much less setup overhead. Do the math
This is an assertion for which evidence is thin. For what O(n log n) sorts is this true? My experience with algorithms I have been measuring lately is that for very small n, the performance of sorts is indistinguishable, but not that O(n2) sorts were faster.
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Evidence is not the issue. A computation of the order statistic is sufficient.
Gus Gustafson
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Depends.
It's a good "teaching algorithm" because it's simple to understand, simple to implement, simple to debug - and it's pretty immediate that you can see results. For a new coder, that's good.
Bubble sort is a lot more complex: it uses a large number of concepts as well as memory so it isn't so applicable to learners.
But...bubble sort works, and if you need to sort a small number of items and can't use standard library routines then it's fine, and I have implemented it a number of times in a number of assembly languages.
These days, most people have access to libraries, and don't have to code sort methods anymore!
Bad command or file name. Bad, bad command! Sit! Stay! Staaaay...
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I asked myself the same questions.
In the very old days when people had to solder together their computers, you got most code from photocopied newsletters and books like this[^].
Typing in your code from all those dubious sources was the way to go and everyone and his dog had to publish an 'optimized' version of bubble sort. I think it has become some kind of tradition or running gag and by the way a metric to identify the members of the 'It's sooooo easy to implement in BASIC' fraction.
The language is JavaScript. that of Mordor, which I will not utter here
This is Javascript. If you put big wheels and a racing stripe on a golf cart, it's still a f***ing golf cart.
"I don't know, extraterrestrial?"
"You mean like from space?"
"No, from Canada."
If software development were a circus, we would all be the clowns.
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There is nothing wrong with using a simple algorithm that you understand and that is adequate to the task. It sometimes easier to write a simple bubble sort than to do the work of interfacing with a library function.
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Not all people in this world are computer scientists. There are different mortals like me whose formal education is in mechanical engineering.
For us, things need to be simple and 'relatable'. Bubble sort is great in these respects. Analogous to the evolution of machines, where they started with simple workable stuff, and gradually increased the efficiency.
Understanding a subject from a historical, evolutionary perspective is likely to give a better insight into how things work.
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Your definitely on to something. A while back I read great series of articles about this at Dr. Dobb's magazine.
Andrew Koenig on Dr. Dobb's Journal discussed this exact subject.
There are a series of articles starting with this one on why bubble sort is slow, but often used...
http://www.drdobbs.com/cpp/teaching-c-badly-how-to-sort-slowly/229625601[^]
http://www.drdobbs.com/cpp/more-thoughts-on-sorting/229700303[^]
The main point being:
"Students tend to use the first technique they learn long after they should have outgrown it."
The Right Way To Teach Sorting - Dr. Dobb's mag[^]
Teaching using bubble sort now is really a hold-over from times past.
Now, there are built in algorithms that do the work much more efficiently.
Basically, he mentions that often programmer's learn the bubble sort first and then don't go on to learn better ways so it can cause issues. He says, teach the use of the built-in algorithms and then teach how the algorithms are written.
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Bubble sort is kinda bad even for an O(n²) algorithm. It's not the shortest code, not the easiest to understand, not even the fastest on average quadratic time sorting algorithm. As far as I can tell the only thing it has going for it is that it's the most popular one.
Combsort is a large improvement over bubble sort, but still small code.
Shellsort deserves to be more widely known even though it isn't optimal, because it's the simplest way to get a worst case better than quadratic.
If you're going to learn a "dumb sort" anyway, learn insertion sort - you will actually use it someday.
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Of course the way BS (don't excuse that pun) uses to test if two items needs swapping is still the fastest way to test if a list is already sorted.
I can only think of one sort of scenario (other than very small lists/arrays where it may or may not perform faster than insertion sort): When sorting directly on a sequential streaming media (such as a tape drive) with too little RAM/Secondary (random access) storage to enable reading the entire contents at once.
swampwiz wrote: So I wonder why is bubble sort even taught?
Mainly as a means to introduce the thought processes around algorithmic optimizations, not so much to teach "a sorting algorithm", but rather to teach how to recognise stuff such as O(N), O(log N), O(N logl N), O(N^2), etc... It's very simple to understand and implement, while some of the divide-n-conquer stuff is pretty complex (especially for beginners).
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swampwiz wrote: suppose that back in the quaint days of "book distribution" (i.e., the only inexpensive way to transfer program code was to put it in a book and have the user type it in
No, it was always a poor example of a sort algorithm, even in the memory constrained days, and was always presented as such in my experience. It was, however, a good introduction to nested loops, algorithm analysis, and, oh yes, concepts of sorting.
Most discussions, especially the algorithm analysis ones, ended with a discussion of how insertion sort was much better, and that quicksort was even better if you could keep the entire dataset in memory and could afford the complexity.
We can program with only 1's, but if all you've got are zeros, you've got nothing.
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