Let us learn from each other here. Tell us about the toughest algorithm you've ever worked on and if you wish, explain how it works and the difficulties you faced.

Any language is allowed

Tell us yours first

(When i am still a Beginner)
Implementing a (GUI) Calendar in Java is the toughest thing i ever come acrossed, it took me 3days... But i learn a lot of things from it too.

Often, one's toughest algorithm problem is often a piece of cake for another.

Personally, I found advanced cases of multidimensional dimensional arrays to be both exciting and intimidating

CRAZYMADMAN:
Often, one's toughest algorithm problem is often a piece of cake for another.

Personally, I found advanced cases of multidimensional dimensional arrays to be both exciting and intimidating

I have less wahala with that..

Multi-level marketing. When you have to do a maybe 4 x 4 force matrix system.

This means when a person registers, you must get like 4 other below below you to complete level 1, each one of them must get 4 each to complete their level 1 for you to get to level 2.
Then you need to calculate the commission that everyone gets based on how their tree looks like. In short, there is a lot of recursion - and recursion programming is not an easy one at all at all. . . .

https://jam.jrox.com/kb/article/110/what-is-forced-matrix.php?action=displayarticle&id=what

dhtml18:
Multi-level marketing. When you have to do a maybe 4 x 4 force matrix system.

This means when a person registers, you must get like 4 other below below you to complete level 1, each one of them must get 4 each to complete their level 1 for you to get to level 2.
Then you need to calculate the commission that everyone gets based on how their tree looks like. In short, there is a lot of recursion - and recursion programming is not an easy one at all at all. . . .

https://jam.jrox.com/kb/article/110/what-is-forced-matrix.php?action=displayarticle&id=what

Its Thinkable Sha

Of course i got it right in the end - after many trials and errors. . . .the second one was when i had to parse an excel document with thousands of rows and columns. . . .and also use google map to get the geographical map area of each record.

hahaha well I must confess, multidimensional arrays have always intimidated me. The toughest single algorithm I'veworked on was in a word unscrambler app. Where the user would input random characters and it would check each one against a dictionary word. One of the problems I had was if the word had a repeated character e.g "advantage". The next one was in a game I made with processing, I'll post about that later.

i have tackled some terrible algorithms especially when consuming web services but i think one that nearly buckled me was traversing DRUPAL'S monstrous multidimensional arrays to capture n process some data during drupal development (while building drupal theme, i refused to meddle into module development for now). finding, tracking and hooking data n processes(functions/methods) into drupal ecosystem is my new found love.

^^^Chisox! the first time i had to walk through that array i almost died. I have missed drupal gan ni o.
One of the toughest jobs I did with drupal was the drupal backend of interswitchng.com - almost killed especially as they wanted everything on the same page.

lol that sounds tough. I don't know why I just don't like arrays in multi dimension

^^^I can cope with arrays of any dimensions in any programming language for that matter - even 1000 levels sef. I may have to take a week off work to parse all the levels, i dont mind really.
But the one i am very mindful of is - recursive programming!!! It makes my head to spin like tire and when i finish. . . . . .i feel quite giddy as if a thousand bees are buzzing in my head. . . . .and sometimes it may cause NIGHTMARES!

lol, true its quite confusing, like I'll have to start writing things down, but I love it . I'm might just make another opensource program using it

dhtml18:
^^^I can cope with arrays of any dimensions in any programming language for that matter - even 1000 levels sef. I may have to take a week off work to parse all the levels, i dont mind really.
But the one i am very mindful of is - recursive programming!!! It makes my head to spin like tire and when i finish. . . . . .i feel quite giddy as if a thousand bees are buzzing in my head. . . . .and sometimes it may cause NIGHTMARES!

One of my toughest algorithm is a program to generate sets of all the possible outcomes of n dice thrown. Where n is any positive integer entered by user. It might be piece of cake for some people though.

Also, there is another like a quiz here https://www.nairaland.com/1486507/challenge-league-fixture-algorithm#19095756

It's more of heuristics though.

Boss I hail oh

ToyinDipo:
One of my toughest algorithm is a program to generate sets of all the possible outcomes of n dice thrown. Where n is any positive integer entered by user. It might be piece of cake for some people though.

Also, there is another like a quiz here https://www.nairaland.com/1486507/challenge-league-fixture-algorithm#19095756

It's more of heuristics though.

hisabimbola:
Boss I hail oh

My Oga, how did thou find me. I be learner for your sideoo.

You guys no dey sleep ni?

haaa DADDIES are here oo

My toughest was when i was building a wordpress plugin (My First) for a client.. the plugin notifies all the mobile app users for the blog (through Push Notification) when a new post is made by the admin, it sends the post title, Intro content and comments count.... i didnt shut down my laptop for a week was hibernating.. (If i was my own project its normal) my browser tab(s) on wordpress documentation, google gcm and apple push and windows was more than 40... after the project when i tried shutting down it took 30mins for my pc to shut down..

^^^Wow! learning GCM under such a short time no easy at all. . . . .hope the client paid well sha.

dhtml18:
^^^Wow! learning GCM under such a short time no easy at all. . . . .hope the client paid well sha.

23 steps is involved (java) www.appsrox.com/android/tutorials/instachat/#1

dhtml18:
^^^Wow! learning GCM under such a short time no easy at all. . . . .hope the client paid well sha.

Why not .... Creating a plugin that uses GCM, APN and the windows Azure service with php curl is no joke...

proxy20:

23 steps is involved www.appsrox.com/android/tutorials/instachat/#1

GCM Alone with PHP is easy....

At all

thewebcraft:

Why not .... Creating a plugin that uses GCM, APN and the windows Azure service with php curl is no joke...

FincoApps:
At all

Hello Boss

I find implementing regular expression based algorithms brain bleeding

Watsup webcraft. I see your web-slaughtering in action o

thewebcraft:

Hello Boss

lol, there's a lot of tough algorithms though.

JackOfAllTrades:
I find implementing regular expression based algorithms brain bleeding

job vacancy at Google Inc apply now if you are qualified for us citizens only https://www.google.com/about/careers/search#!t=jo&jid=120105001

FincoApps:
Watsup webcraft. I see your web-slaughtering in action o

Lolzz....

dhtml18:
^^^I can cope with arrays of any dimensions in any programming language for that matter - even 1000 levels sef. I may have to take a week off work to parse all the levels, i dont mind really.
But the one i am very mindful of is - recursive programming!!! It makes my head to spin like tire and when i finish. . . . . .i feel quite giddy as if a thousand bees are buzzing in my head. . . . .and sometimes it may cause NIGHTMARES!

theoritically. any recursive function or situation can be done with iterative methods if restructured properly. just that recursion makes ur code more ELEGANT though not intuitive (even when heavily commented as refactoring may be a nightmare for another person or even u after some time).

i have never use recursion since i have not encounter a suitable use - case where iterative method is not suitable to deal with it. just ma opinion anyway