Comments on: Friday Algorithms: Sorting a Set of Integers – Far Quicker than Quicksort!

By: Amadeus

Amadeus — Mon, 29 Jan 2018 12:16:50 +0000

This is the best explanation I have found so far of this algorithm. Well done and thank you.

By: Stoimen

Stoimen — Thu, 27 Oct 2011 09:33:37 +0000

@Eddy Vang – first of all do you think this code is maintainable? Yes, it’s javascript so it should be minified. What about “function s(a) …” ;)?

However by saying “faster” do you consider the speed of Math functions? Have you benchmarked this code?

By: Eddy Vang

Eddy Vang — Thu, 27 Oct 2011 00:46:55 +0000

Even smaller

function sort(a){var d=[],o=[],e=Math.min.apply(Math,a),g=Math.max.apply(Math,a);for(var i in a)d[a[i]]=1;do d[e]&&o.push(e);while(e++

By: Eddy Vang

Eddy Vang — Thu, 27 Oct 2011 00:31:14 +0000

CORRECTION. Looks like this form doesn’t like — or minus minus.

My code suppose to be while(c–); //c minus minus
and NOT while(c–); //WRONG from auto correct

By: Eddy Vang

Eddy Vang — Thu, 27 Oct 2011 00:21:47 +0000

Here's a faster and smaller version.

function sort(a){
    var d=[],f=[],e=Math.min.apply(Math,a),g=Math.max.apply(Math,a),c=g-1;
    do d[c]=0;while(c--);
    for(c in a)d[a[c]]=1;
    do d[e]&&f.push(e);while(e++<g);
    return f
};

By: vince

vince — Fri, 14 Oct 2011 06:28:47 +0000

thanks for this post i pass my project it is good

By: Paul

Paul — Mon, 28 Jun 2010 17:30:58 +0000

FYI, this tends to be really slow in JavaScript. JS uses hashs for their arrays, so what should be O(n) becomes O(n log n). In IE, it’s even worse because they use linked lists. So O(n) becomes O(n^2) or worse.

I remember using this Radix trick on my professors in school to be a prick. It was always fun to make them include a memory big-O with their questions.

By: Kevin

Kevin — Sun, 27 Jun 2010 02:23:30 +0000

Also known as bitmap sort. This algorithm is very useful if you want to sort integers in a range and when you have to use minimal primary memory but have secondary memory available.

By: Stoimen

Stoimen — Sat, 26 Jun 2010 06:52:32 +0000

@Matthew – thanks for the comment – I completely agree with you! Indeed sometimes choosing an algorithm is as difficult as the implementation itself!

By: Stoimen

Stoimen — Sat, 26 Jun 2010 06:50:59 +0000

@kjordan – of course this is an algorithm using transformation instead of comparison like the quicksort, and thus it’s using more memory. That’s why you should be very careful when choosing this algorithm!