minimum travel from point to point with incremental steps

It’s my first time to make a question here. I have a curious problem about algorithm, in the center of Cartesian plane (0,0) I need to go to another point (x,y) but I only can use horizontaly and verticaly steps and this steps increases one by one.

For example, I need to go to (1,1) point and steps are:

  • Go to (1,0), a step of 1 unit.
  • Go to (1,-2) a step of 2 units.
  • Finally, go to (1,1) a step of 3 units.

Obviously, there are several ways to go to a point from center but the problem needs the minimal.

Are there a formula or an algorithm to answer this question? Thanks for read this and for your questions.

Incremental dynamic on-disk disjoint sets (incremental on-disk dynamic forest)


Problem statement

I am looking for an algorithm to maintain a very large number of disjoint sets under node and edge additions. Due to the data size, keeping everything in memory is not feasible, so the algorithm needs to work efficiently with SSD storage.

Ideally, the algorithm should:

  • support link(v1, v2) operation which either merges two sets or does nothing if v1 and v2 already belong to the same set. If either v1 or v2 did not exist prior to link operation, the new vertex(es) should be added to a set
  • support get_set(v) operation which will return all elements in a set
  • be IO efficient in terms of SSD access
  • allow concurrent link and get_set operations

Some notes:

  • only edge additions are allowed, no removals
  • consecutive link operations 1..N operate on a small number of disjoint sets K, K << N

Why I need such an algorithm

There is a stream of events (~100M of events per day) in which each event may link to zero or several “parent” events. When a new event arrives, I need to run some aggregations on a graph that this event belongs to. Events are generated by a set of services, so this is basically a distributed tracing problem.

How to implement Incremental Advancement in D&D 5th edition

I’m starting off a new 5th edition campaign, which will hopefully be running long term. We’ve played some 13th Age and one of the things the players really enjoyed was the Incremental advancement system.

In 13th Age, at certain milestones (we used the end of every session), characters can take on an aspect of their next level. This includes a bonus to attack/defense, extra hit points, talents, powers, a feat or an ability bonus, or an icon relationship.

It seems that just about every class in 5th edition gains something at every level, whether it be new spells, class features, or proficiency bonus. We’re also planning on porting icon relationships over, so that will be an option for at least a few of the level ups.

Does 5th edition have an equivalent/ comparable incremental advance system that would keep the same feel? I don’t currently have the DMG, so an answer that simply states this information exists and gives a page number would be acceptable.

If it doesn’t currently come pre-packaged with 5th edition, are there any major issues with implementing the incremental advance system as it stands into 5th edition? Is access to higher level features/ spells going to majorly unbalance the classes compared to each other? Are there few enough class features per level that incremental advance is unnecessary?

I’m expecting the PC’s to level up every 3-4 sessions, if that changes any of the answers.

SharePoint 2016 scheduled incremental crawls are not running

  • SharePoint 2016 MinRole Farm with latest patch KB4475590 (September/2019) Security update for SharePoint Enterprise Server 2016 Core.
  • Scheduled incremental crawls are not running even though in Central Administration the Next Incremental crawl date and time gets updated in the Manage Content Sources view, but nothing really happens.
  • If I manually trigger an incremental crawl to run it works fine.
  • No errors are being logged in ULS Logs or in event viewer.
  • Indexing Schedule Manager Timer Job on the Search Server is not running, even when I click on Run Now, it doesn’t seem to work.
  • In Central Administration>Server in Farm, the server with Role Application with Search is showing Compliant: No (Fix) and I’ve clicked on the Fix link and after it runs for a while, the Compliant status doesn’t change to Yes.

Things I’ve tried to troubleshoot the issue with no success:

  • Stop search services on the server and Timer service, clearing config cache and restarting all services.

  • index reset, run full crawl after that manually and set up the scheduled incremental crawl, which will not run neither.

  • created a new Content Source and set up the incremental crawls to see if it will run in this new content source and that didn’t happen neither.

Any idea or suggestions about what the issue is and how to fix it?

How to implement an incremental backup strategy? [on hold]

We have a project where we need a backup solution to backup websites. It is basically files and a SQL database.

The websites are running PHP. We can only get in touch with the website through HTTP(S). No (S)FTP or SSH. We have no control to the server configuration. See the problem as it is a WordPress website where the owner will install a plugin. Therefore, that explains the no FTP/SSH constraint.

We did not found any solution that fit that.

The tasks:

  • Get the (modified) files
  • Store them
  • Reassemble a backup when needed.

We must be able to restore a website from any point with the last 365 days.

What are the possible strategies to store incremental file backups and be able to reassemble the incremental backup EFFICIENTLY when needed (one zip file) ?

In other words, how do you store the increments you get in a way to make things simple and be able to reassemble the increments as fast as possible.

How to implement a good incremental backup strategy? [on hold]

We have a project where we need a backup solution to backup websites. It is basically files and a SQL database.

The websites are running PHP. We can only get in touch with the website through HTTP(S). No (S)FTP or SSH. We have no control to the server configuration. Let’s assume our sites are on a shared hosting.

I have not seen any solution on the market where we can ask the provider to contact the website through HTTP(S) to initiate the process and ask a script on the web server to push files to the backup solution.

I came up with that scenario to solve the issue:

  1. Initially, the backup server calls the web server and asks for a full backup.
  2. The web server responds by dumping the database in a file and pushes it to the backup server.
  3. The web server also sends all files through HTTP.
  4. The backup server receive every file, stores them, and gets a hash for each file.
  5. Process completed.

The next time a backup is required, here is what happen:

  1. The backup server calls the web server and asks for an incremental backup. The backup server includes a file containing all files hashes.
  2. The web server dumps the full database and pushes it to the backup server.
  3. The web server browse every file and looks for file that have a different hash from what was sent from the backup server (modified file), files that are not already in the list (added file), files that are in the list but no longer on the file system (deleted file). Files are pushed accordingly.
  4. The backup server receive every file, stores them, and gets a hash for each file.
  5. Process completed.

We must be able to restore a website from any point with the last 365 days.

Here are my questions:

  1. Are these scenarios viable?
  2. Where can I find information about “how to implement an incremental backup solution on the backup server”? I’m looking for in-depth explanation or implementation. Not some basic article about “what is an incremental backup”.
  3. What is a good strategy to store the backups… but also to restore efficiently?

Do not hesitate if you need more details. I try to give not too much information as I don’t want to add constraints.