Details
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SkillsRHCEJava,Python.
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LocationIndia
Joined devRant on 6/4/2016
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So I made a couple slight modifications to the formula in the previous post and got some pretty cool results.
The original post is here:
https://devrant.com/rants/5632235/...
The default transformation from p, to the new product (call it p2) leads to *very* large products (even for products of the first 100 primes).
Take for example
a = 6229, b = 10477, p = a*b = 65261233
While the new product the formula generates, has a factor tree that contains our factor (a), the product is huge.
How huge?
6489397687944607231601420206388875594346703505936926682969449167115933666916914363806993605...
and
So huge I put the whole number in a pastebin here:
https://pastebin.com/1bC5kqGH
Now, that number DOES contain our example factor 6229. I demonstrated that in the prior post.
But first, it's huge, 2972 digits long, and second, many of its factors are huge too.
Right from the get go I had hunch, and did (p2 mod p) and the result was surprisingly small, much closer to the original product. Then just to see what happens I subtracted this result from the original product.
The modification looks like this:
(p-(((abs(((((p)-(9**i)-9)+1))-((((9**i)-(p)-9)-2)))-p+1)-p)%p))
The result is '49856916'
Thats within the ballpark of our original product.
And then I factored it.
1, 2, 3, 4, 6, 12, 23, 29, 46, 58, 69, 87, 92, 116, 138, 174, 276, 348, 667, 1334, 2001, 2668, 4002, 6229, 8004, 12458, 18687, 24916, 37374, 74748, 143267, 180641, 286534, 361282, 429801, 541923, 573068, 722564, 859602, 1083846, 1719204, 2167692, 4154743, 8309486, 12464229, 16618972, 24928458, 49856916
Well damn. It's not a-smooth or b-smooth (where 'smoothness' is defined as 'all factors are beneath some number n')
but this is far more approachable than just factoring the original product.
It still requires a value of i equal to
i = floor(a/2)
But the results are actually factorable now if this works for other products.
I rewrote the script and tested on a couple million products and added decimal support, and I'm happy to report it works.
Script is posted here if you want to test it yourself:
https://pastebin.com/RNu1iiQ8
What I'll do next is probably add some basic factorization of trivial primes
(say the first 100), and then figure out the average number of factors in each derived product.
I'm also still working on getting to values of i < a/2, but only having sporadic success.
It also means *very* large numbers (either a subset of them or universally) with *lots* of factors may be reducible to unique products with just two non-trivial factors, but thats a big question mark for now.
@scor if you want to take a look.5 -
Can anyone recommend a good vps/dedicated server hoster for east us? I looking for a machine with 8 cores, 32gb memory and 2x 1,9tb nvme ssds. AWS, Azure and Google are way too expencive. In Germany we use the ax61-nvme instance of hetzner which costs around 100$.
Thanks for any advises✌️5 -
A word of advice to any new Arch user: don't use lxdm for your display manager. It's utter shit. The package hijacks the symlink of any other DM when you install it, and it refocuses the DM on a 5 second loop while it's running, making it a pain in the ass to use a VT. LightDM was broken temporarily so I had to install it, but frankly, I don't ever want to touch thiis piece of software again.4
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Today I'm ranting about Windows. No, it's not "WiNdOwS sUcKs!", it's more like "But why!?"
See, I'm an IT guy for the year, and in my office they use Windows. Now once upon a time, they had Active Directory and all that (well, actually, they still do) but then they got some new computers running Windows 10, and for some reason they just couldn't join them to the domain!
Why can't they, you ask? Well, Microsoft only allows Win 10 Pro and up to join a Domain, and since these computers came with Win 10 Home, that wasn't possible.
Long story short, I now have some 30 computers that need to be upgraded (possibly from 7) to Win 10 Pro, and joined to the Domain.
Thing is, I would like to do that all in one go, so I look into how to automatically setup Windows.
"Ah! Got it, provisioning packages!"
Lest you think they work let me spare you now: they don't. Just like real computers where everything is different, provisioning packages failed to work twice, and after wasting about a week trying to make it work, I gave up.
So now I realized that I need to try a different method, a custom windows image. Issue is, I've got no clue how to make one. See, microsoft decided to go all in on the provisioning packages thing (they do have advantages in certain use cases), and seemed to decide that making custom images was no longer necessary, so they documentation was nearly impossible to find.
But after a lot of searching, I figured out how to do it:
1. Install Windows in a VM.
2. Put it in audit mode.
3. Install your stuff.
4. Create an unattend.xml file with certain customizations.
5. Put the unattend in Windows\System32\Sysprep
6. Generalize the image.
7. Boot WinPE.
8. Open the console.
9. Capture the image.
10. Wait an hour or two.
11. Done!
I'm over simplifying, it was a huge PITA, and yet there were still issues.
Maybe another time I'll talk about those.22 -
The statement is : if you ever feel useless, then you haven't seen this simplification, well... just see who will be more useless to solve it at same place again...4
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The first time I realized I wasn't as good as I thought I was when I met the smartest dev I've ever known (to this day).
I was hired to manage his team but was just immediately floored by the sheer knowledge and skills this guy displayed.
I started to wonder why they hired outside of the team instead of promoting him when I found that he just didn't mesh well with others.
He was very blunt about everything he says. Especially when it comes to code reviews. Man, he did /not/ mince words. And, of course, everyone took this as him just being an asshole.
But being an expert asshole myself, I could tell he wasn't really trying to be one and he was just quirky. He was really good and I really liked hanging out with him. I learned A LOT of things.
Can you imagine coming into a lead position, with years of experience in the role backing your confidence and then be told that your code is bad and then, systematically, very precisely, and very clearly be told why? That shit is humbling.
But it was the good kind of humbling, you know? I really liked that I had someone who could actually teach me new things.
So we hung out a lot and later on I got to meet his daughter and wife who told me that he had slight autism which is why he talked the way he did. He simply doesn't know how to talk any other way.
I explained it to the rest of the team (after getting permission) and once they understood that they started to take his criticism more seriously. He also started to learn to be less harsh with his words.
We developed some really nice friendships and our team was becoming a little family.
Year and a half later I had to leave the company for personal reasons. But before I did I convinced our boss to get him to replace me. The team was behind him now and he easily handled it like a pro.
That was 5 years ago. I moved out of the city, moved back, and got a job at another company.
Four months ago, he called me up and said he had three reasons for us to meet up.
1. He was making me god father of his new baby boy
2. That they created a new position for him at the company; VP of Engineering
and
3. He wanted to hang out
So we did and turns out he had a 4th reason; He had a nice job offer for me.
I'm telling this story now because I wanted to remind everyone of the lesson that every mainstream anime tells us:
Never underestimate the power of friendship.21 -
Wrote a python script to fetch details of amazon products to monitor price differences.
The script is only 50 lines, which is why I love python!8 -
Java interested folks.
I recommend reading Effective Java by Joshua Bloch.
It's worth reading.
Even James Gosling praised this book.12 -
De-google your life
Search:
-qwant
-startpage
-searx
-duck duck go look up the founder
-yandex (putin botnet)
Mail
-cock.li
-ProtonMail
-Posteo
-Tutanota
-your own
Browsers
-https://kek.gg/i/3g2z6d.png (superior list)
-https://kek.gg/i/67YQQx.jpg (for furfags)
-https://wiki.installgentoo.com/inde...
/Web_browsers
Collaborative documents
-quip
-turtl
-ether pad (eg: notes.typo3.org or etherpad.net)
-microsoft office online (lol)
Image Upload/Edit
-kek.gg
Video sharing
-hooktube
-bitchute.com
-vid.me
-dtube.video
Social
-gnu social (for freedom loving patriots)
-mastodon (for proprietary loving gook pedos and sjws)
-gab.ai
-minds
-diaspora
Image Upload/Edit
-kek.gg
Google CDN avoidance
-Decentraleyes
Ad and script blocking
-uBlock Origin
Share links without gibbing clicks
-archive.is
Android
-droid-break.info
How to hosts file (lol, just block google bro):
-https://archive.is/gBJ8i
Reading:
-https://wiki.installgentoo.com/inde...
/Anonymizing_yourself#Fingerprinting
-https://wiki.installgentoo.com/inde...
/Firefox#Notable_add-ons
-https://panopticlick.eff.org77 -
If Programming Languages Were Girls:
Java: Your current girlfriend, you've been going steady for a while now. Things are okay.
Kotlin: The girl Java finds you cheating on, she's just amazing, and you wish you'd met her sooner.
Visual Basic: The girl you accidentally started a relationship with because you didn't know how to say no. But quickly realised your mistake and regretted it.
JavaScript: A childhood friend you occasionally hook up with. But you could never settle for a relationship with them.
Python: A bossy, manipulative girl who quickly turned things sour. But everyone else loves her because of her huge libraries.
-----------------------------------------------------
My and a co worker were joking the other day about what programming languages would be like if they were girls. This is what we came up with (Original inspiration: the Distracted Boyfriend meme (Feel free to add your own!)).49 -
My great uncle came over this weekend, and he is a big Apple fan though he owns a little hp. He asked me if I knew windows ten, to which I said yes, and then said he had a problem. His internet wouldn't connect. I came to his laptop, and he already had the wifi menu up, which said in big letters "Your WiFi is turned off." So I said to him "Your WiFi is turned off." He proclaimed his disdain for "the software" and asked if I could fix it. Instead of clicking the very obvious button that took maybe 10% of his screen, I opened command prompt as admin and entered "netsh interface show interface" followed by "netsh interface set interface Wi-Fi enabled"
I followed it up by saying I fixed a problem with his wireless card and that he should be able to use the large wifi button that appears when he opens the menu to turn it off and on again5 -
I was registering for a website, and on a whim, I used this as my username:
null'); PRINT('Hello');--
And sure enough, the login system went down. The next day it was still down, so I went to Twitter to tell the people running the site that this was why, but to my surprise, I see them saying they had been hacked.
Based on the timing, I'm pretty sure they're referring to this, but they are saying user info was stolen. *facepalm*
They later said they stored passwords salted with a fixed salt and hashed with fucking md5, at which point I was glad not to have done any more business with them.
How incompetent can these fucking people be?!14 -
Don't tell them to run "rm -rf /" as root. That's too nice. There might be inodes left on the hard drive.
MAKE IT WORSE:
"cat /dev/zero > /dev/sda" as root.
LEAVE NOTHING.13 -
If Doctors Were Like Coders
(cross-posted from https://medium.com/@c09b6133a238/...)
Problem: The patient has a broken leg.
Solution:
1. Ask the patient to reproduce the exact scenario that resulted in the broken leg. Watch closely to see if the leg breaks again. Check for consistency by repeating the scenario a few more times.
2. Explain that this isn’t an intended use case for the leg, and besides, it only affects one person. Ask the patient if, all things considered, he really wants to prioritize his broken leg over your other work.
3. Point out that the patient’s other leg performs just fine under the same circumstances. Ask if he can use his other leg instead, at least as a workaround.
4. Attach several accelerometers to the broken leg and break it again. Stare at the data received from the accelerometers, then shrug and declare it useless.
5. Decide that the patient’s problem must be in his spleen. After all, that’s the only part of his body you don’t really understand.
6. Track down the people who created the patient. Ask them if he’s ever had spleen problems before. When they seem confused, explain that he has a broken leg. Ignore them when they tell you that the spleen they created could not possibly cause a broken leg.
7. Ask Google where a person’s spleen is. Spend half an hour reading the Wikipedia article on Splenomegaly.
8. Open the patient and grumble about how tightly-coupled his spleen and circulatory system are. Examine the spleen’s outer surface to see if there are any obvious problems. Inform him that several of his organs are very old and he should consider replacing them with something more modern.
9. Compare the spleen to some pictures of spleens online. If anything looks different, try to make it look the same.
10. Remove the spleen completely. See if the patient’s leg is still broken. If so, put the spleen back in.
11. Tell the patient that you’ve noticed his body is made almost entirely out of cellular tissue, whereas most bodies these days are made out of cardboard. Explain that cardboard is a lot easier for beginners to understand, it’s more forgiving of newbie mistakes, and it’s the tissue franca of the Internet. Ask if he’d like you to rebuild his body with cardboard. It will take you longer, but then his body would be future-proof and dead simple. He could probably even fix it himself the next time it breaks.
12. Spend some time exploring the lymph nodes in the patient’s abdominal cavity. Accidentally discover that if the patient’s leg is held immobile for six weeks, it gets better.
13. Charge the patient for six weeks of work.14 -
Got this from a recruiter:
We are looking for a **Senior Android Developer/Lead** at Philadelphia PA
Hiring Mode: Contract
Must have skills:
· 10-12 years mobile experience in developing Android applications
· Solid understanding of Android SDK on frameworks such as: UIKit, CoreData, CoreFoundation, Network Programming, etc.
· Good Knowledge on REST Ful API and JSON Parsing
· Good knowledge on multi-threaded environment and grand central dispatch
· Advanced object-oriented programming and knowledge of design patterns
· Ability to write clean, well-documented, object-oriented code
· Ability to work independently
· Experience with Agile Driven Development
· Up to date with the latest mobile technology and development trends
· Passion for software development- embracing every challenge with a drive to solve it
· Engaging communication skills
My response:
I am terribly sorry but I am completely not interested in working for anyone who might think that this is a job description for an Android engineer.
1. Android was released in September 2008 so finding anyone with 10 years experience now would have to be a Google engineer.
2. UIKit, CoreData, CoreFoundation are all iOS frameworks
3. Grand Central Dispatch is an iOS mechanism for multithreading and is not in Android
4. There are JSON parsing frameworks, no one does that by hand anymore
Please delete me from your emailing list.49 -
A story about how a busy programmer became responsible for training interns.
So I was put in charge of a team of interns and had to teach them to work with Linux, coding (Bash, Python and JS) and networking overall.
None of the interns had any technical experience, skills, knowledge or talent.
Furthermore the task came to me as a surprise and I didn't have any training plan nor the time.
Case 0:
Intern is asked to connect to a VM, see which interfaces there are and bring up the one that's down (eth1). He shuts eth0 down and is immediately disconnected from the machine, being unable to connect remotely.
Case 1:
Intern researches Bash scripting via a weird android app and after a hour or so creates and runs this function: test(){test|test&}
He fork-bombed the VM all other interns used.
Case 2:
All interns used the same VM despite the fact that I created one for each.
They saved the same ssh address in Putty while giving it different names.
Case 3:
After explicitly explaining and demonstrating to the interns how to connect to their own VMs they all connect to the same machine and attempt to create file systems, map them and etc. One intern keeps running "shutdown -r" in order to test the delay flag, which he never even included.
Case 4:
All of the interns still somehow connect to the same VM despite me manually configuring their Putty "favorites". Apparently they copy-paste a dns that one of them sent to the entire team via mail. He also learned about the wall command and keeps scaring his team members with fake warnings. A female intern actually asked me "how does the screen knows what I look like?!". This after she got a wall message telling her to eat less because she gained weight.
Case 5:
The most motivated intern ran "rm -rf" from his /etc directory.
P.S. All other interns got disconnected because they still keep using his VM.
Case 6:
While giving them a presentation about cryptography and explaining how SSH (that they've been using for the past two weeks) works an intern asked "So is this like Gmail?".
I gave him the benefit of the doubt and asked if he meant the authorization process. He replied with a stupid smile "No! I mean that it can send things!".
FML. I have a huge project to finish and have to babysit these art majors who decided to earn "ezy cash many" in hightech.
Adventures will be continued.26 -
> Customer calls
Her: I have over 5k 404 request to [insertwebsite]/autodiscover/autodiscover.xml
Me: Sound like a missconfigured exchangeserver/client. Let me have a look.
> Takes a look and can confirm the IP and the owner of that IP
Me: It looks like someone/something from xxx.xxx.xxx.xxx is failing to resolve autodiscover.[insertdomain].com
and defaults to @ record on the zone. Do you happend to know to whom that IP belongs?
Her: No, and I dont care, just block it. I do not like the 404 that shows up on the summary.
Me: Alright
> Blocks the IP in the firewall.
>>> Fast forward to next day >>>
> Someone calls, it is the same girl
Her: I cant reach my website! Infact, I cant reach anything! WHYYYYYY!!!
> I remember, blocking that IP yesterday...
Me: Oh, can you please visist "minip.se" (whatismyip.com, swedish version) and tell me what you see?
Her: Yes, it is xxx.xxx.xxx.xxx
Me: Do you remember that IP that you request that I block yesterday?
> I can hear the shame coming from the phone.
> Turn out that her collegues did'nt have any mail delivered to them from the time I blocked their IP
> Her boss is really mad
> Atleast she had a cute voice12 -
I just started playing around with machine learning in Python today. It's so fucking amazing, man!
All the concepts that come up when you search for tutorials on YouTube (you know, neural networks, SVM, Linear/Logic regression and all that fun stuff) seem overwhelming at first. I must admit, it took me more than 5 hours just to get everything set up the way it should be but, the end result was so satisfying when it finally worked (after ~100 errors).
If any of you guys want to start, I suggest visiting these YouTube channels:
- https://youtube.com/channel/...
- http://youtube.com/playlist/...9 -
You go to an accountant to file your itemized taxes in a couple of hours, you pay them at least $200.
You go to a lawyer to incorporate your business in 2 days, and you pay at least $800.
You hire a photographer to take pictures of your 4-hours wedding and you pay them at least $1500.
You go to your car dealership to fix something and they charge you about $125 hourly labor rate.
Now, ENLIGHTEN ME, how did you come up with the idea that the web application I will create for your business in 8 weeks (design, code, test, deploy, server administration) should not cost more than $500????!!!!!18 -
Not sure what Linux Desktop to use? Use this handy guide:
- GNOME: when you want no tray icons, themes that break every minor GTK release, and extensions for basic features (that are buggy.)
- KDE: pretty go-Segmentation Fault
- DWM/Awesome/i3/etc.: when you feel like the time you spent learning Vim wasn't wasteful enough
- XFCE: when you want one update per decade and poor Systemd support.
- LXQt: the biggest positive is that it doesn't use GTK.
- Cinnamon: when you like GNOME 3 but you want a different menu
- Deepin: when you want a desktop with the build quality of an HP laptop.
Aren't sure whether to use Xorg or Wayland?
- Xorg: if you want to absurdly fuck up your touchscreen, pick this one.
- Wayland: if you want to screw up most of your apps, too bad; this won't work with your proprietary drivers. If only it did.
What distro to use?
- Ubuntu: if you want to break your system with PPAs, check out this one.
- Debian: when you want Ubuntu except with more out of date packages
- Redhat: when you want Debian except with more out of date packages
- ElementaryOS: wait, someone actually made a properly designed Linux UI?
- Arch Linux: the only thing that doesn't make me sick anymore.
- Slackware: "that exists still really?"
- Gentoo: when you hate systemd more than waiting 4 days to compile Firefox on every release.
... I love Linux. I do. But it is very taxing to get things comfortable for me anymore. I feel like the Linux Desktop is in a period of flux and it's painful to be a part of right now.25 -
Interviewer: Welcome, Mr X. Thanks for dropping by. We like to keep our interviews informal. And even though I have all the power here, and you are nothing but a cretin, let’s pretend we are going to have fun here.
Mr X: Sure, man, whatever.
I: Let’s start with the technical stuff, shall we? Do you know what a linked list is?
X: (Tells what it is).
I: Great. Can you tell me where linked lists are used?
X:: Sure. In interview questions.
I: What?
X: The only time linked lists come up is in interview questions.
I:: That’s not true. They have lots of real world applications. Like, like…. (fumbles)
X:: Like to implement memory allocation in operating systems. But you don’t sell operating systems, do you?
I:: Well… moving on. Do you know what the Big O notation is?
X: Sure. It’s another thing used only in interviews.
I: What?! Not true at all. What if you want to sort a billion records a minute, like Google has to?
X: But you are not Google, are you? You are hiring me to work with 5 year old PHP code, and most of the tasks will be hacking HTML/CSS. Why don’t you ask me something I will actually be doing?
I: (Getting a bit frustrated) Fine. How would you do FooBar in version X of PHP?
X: I would, er, Google that.
I: And how do you call library ABC in PHP?
X: Google?
I: (shocked) OMG. You mean you don’t remember all the 97 million PHP functions, and have to actually Google stuff? What if the Internet goes down?
X: Does it? We’re in the 1st world, aren’t we?
I: Tut, tut. Kids these days. Anyway,looking at your resume, we need at least 7 years of ReactJS. You don’t have that.
X: That’s great, because React came out last year.
I: Excuses, excuses. Let’s ask some lateral thinking questions. How would you go about finding how many piano tuners there are in San Francisco?
X: 37.
I: What?!
X: 37. I googled before coming here. Also Googled other puzzle questions. You can fit 7,895,345 balls in a Boeing 747. Manholes covers are round because that is the shape that won’t fall in. You ask the guard what the other guard would say. You then take the fox across the bridge first, and eat the chicken. As for how to move Mount Fuji, you tell it a sad story.
I: Ooooooooookkkkkaaaayyyyyyy. Right, tell me a bit about yourself.
X: Everything is there in the resume.
I: I mean other than that. What sort of a person are you? What are your hobbies?
X: Japanese culture.
I: Interesting. What specifically?
X: Hentai.
I: What’s hentai?
X: It’s an televised art form.
I: Ok. Now, can you give me an example of a time when you were really challenged?
X: Well, just the other day, a few pennies from my pocket fell behind the sofa. Took me an hour to take them out. Boy was it challenging.
I: I meant technical challenge.
X: I once spent 10 hours installing Windows 10 on a Mac.
I: Why did you do that?
X: I had nothing better to do.
I: Why did you decide to apply to us?
X: The voices in my head told me.
I: What?
X: You advertised a job, so I applied.
I: And why do you want to change your job?
X: Money, baby!
I: (shocked)
X: I mean, I am looking for more lateral changes in a fast moving cloud connected social media agile web 2.0 company.
I: Great. That’s the answer we were looking for. What do you feel about constant overtime?
X: I don’t know. What do you feel about overtime pay?
I: What is your biggest weakness?
X: Kryptonite. Also, ice cream.
I: What are your salary expectations?
X: A million dollars a year, three months paid vacation on the beach, stock options, the lot. Failing that, whatever you have.
I: Great. Any questions for me?
X: No.
I: No? You are supposed to ask me a question, to impress me with your knowledge. I’ll ask you one. Where do you see yourself in 5 years?
X: Doing your job, minus the stupid questions.
I: Get out. Don’t call us, we’ll call you.
All Credit to:
http://pythonforengineers.com/the-p...89