#priorityqueue

[akhilmittal20]

C# Priority List: A Comprehensive Guide

A priority list is a data structure used to store a collection of elements such that each element has a priority associated with it. Priority lists, also known as heaps, are used in many applications such as task scheduling, job scheduling, and resource a

What is a Priority List? A priority list is a data structure used to store a collection of elements such that each element has a priority associated with it. Priority lists, also known as heaps, are used in many applications such as task scheduling, job scheduling, and resource allocation. In C#, the priority list can be implemented using the Priority Queue class. Continue reading Untitled

[javafullstackdev]

JavaCollections: Your Data, Your Way

Master the art of data structures:

List: ArrayList, LinkedList

Set: HashSet, TreeSet

Queue: PriorityQueue, Deque

Map: HashMap, TreeMap

Pro tips:

Use generics for type safety

Choose the right collection for your needs

Leverage stream API for elegant data processing

Collections: Because arrays are so last century.

[praveennareshit]

📚 Comparing Java Collections: Which Data Structure Should You Use?

If you're diving into Core Java, one thing you'll definitely bump into is the Java Collections Framework. From storing a list of names to mapping users with IDs, collections are everywhere. But with all the options like List, Set, Map, and Queue—how do you know which one to pick? 🤯

Don’t worry, I’ve got you covered. Let��s break it down in simple terms, so you can make smart choices for your next Java project.

🔍 What Are Java Collections, Anyway?

The Java Collection Framework is like a big toolbox. Each tool (or data structure) helps you organize and manage your data in a specific way.

Here's the quick lowdown:

List – Ordered, allows duplicates

Set – Unordered, no duplicates

Map – Key-value pairs, keys are unique

Queue – First-In-First-Out (FIFO), or by priority

📌 When to Use What? Let’s Compare!

📝 List – Perfect for Ordered Data

Wanna keep things in order and allow duplicates? Go with a List.

Popular Types:

ArrayList – Fast for reading, not so much for deleting/inserting

LinkedList – Good for frequent insert/delete

Vector – Thread-safe but kinda slow

Stack – Classic LIFO (Last In, First Out)

Use it when:

You want to access elements by index

Duplicates are allowed

Order matters

Code Snippet:

java

🚫 Set – When You Want Only Unique Stuff

No duplicates allowed here! A Set is your go-to when you want clean, unique data.

Popular Types:

HashSet – Super fast, no order

LinkedHashSet – Keeps order

TreeSet – Sorted, but a bit slower

Use it when:

You care about uniqueness

You don’t mind the order (unless using LinkedHashSet)

You want to avoid duplication issues

Code Snippet:

java

🧭 Map – Key-Value Power Couple

Think of a Map like a dictionary. You look up values by their unique keys.

Popular Types:

HashMap – Fastest, not ordered

LinkedHashMap – Keeps insertion order

TreeMap – Sorted keys

ConcurrentHashMap – Thread-safe (great for multi-threaded apps)

Use it when:

You need to pair keys with values

You want fast data retrieval by key

Each key should be unique

Code Snippet:

java

⏳ Queue – For First-Come-First-Serve Vibes

Need to process tasks or requests in order? Use a Queue. It follows FIFO, unless you're working with priorities.

Popular Types:

LinkedList (as Queue) – Classic FIFO

PriorityQueue – Sorted based on priority

ArrayDeque – No capacity limit, faster than LinkedList

ConcurrentLinkedQueue – Thread-safe version

Use it when:

You’re dealing with task scheduling

You want elements processed in the order they come

You need to simulate real-life queues (like print jobs or tasks)

Code Snippet:

java

🧠 Cheat Sheet: Pick Your Collection Wisely

⚙️ Performance Talk: Behind the Scenes

💡 Real-Life Use Cases

Use ArrayList for menu options or dynamic lists.

Use HashSet for email lists to avoid duplicates.

Use HashMap for storing user profiles with IDs.

Use Queue for task managers or background jobs.

🚀 Final Thoughts: Choose Smart, Code Smarter

When you're working with Java Collections, there’s no one-size-fits-all. Pick your structure based on:

What kind of data you’re working with

Whether duplicates or order matter

Performance needs

The better you match the collection to your use case, the cleaner and faster your code will be. Simple as that. 💥

Got questions? Or maybe a favorite Java collection of your own? Drop a comment or reblog and let’s chat! ☕💻

If you'd like me to write a follow-up on concurrent collections, sorting algorithms, or Java 21 updates, just say the word!

✌️ Keep coding, keep learning! For More Info : Core Java Training in KPHB For UpComing Batches : https://linktr.ee/NIT_Training

[programmingandengineering]

Vertex Distance Data Structure

In the Graph class and Dijkstra’s algorithm, you will be using the VertexDistance class implementation that we have provided. In the Graph class, this data structure is used by the adjacency list to represent which vertices a vertex is connected to. In Dijkstra’s algorithm, you should use this data structure along with a PriorityQueue. At any stage throughout the algorithm, the PriorityQueue of…

[dosomedev]

Know what Java PriorityQueue is for?

[devtech-ascendancy-hub]

高效使用阻塞隊列：生產者-消費者模型的最佳實踐 | 阻塞隊列 | 3 種實現

Overview of Content 生產者-消費者模型（Producer-Consumer Model）是一種常見的多執行緒佈局，這裡我們將深入探討其核心元素和應用場景 首先，我們會介紹生產者和消費者這兩個角色，並解釋它們如何通過阻塞隊列進行有效的通信，我們將探討阻塞隊列的特性，特別是其在資源管理中的重要性 接著，我們將詳述不同類型的阻塞隊列，包括 ArrayBlockingQueue、LinkedBlockingQueue、SynchronousQueue 等，分析每種隊列的特性及其適用場景。我們還會對比 ArrayBlockingQueue 和 LinkedBlockingQueue 的鎖機制，幫助您理解它們在多執行緒環境中的不同表現 最後，我們將展示如何實現生產者-消費者模型，包括使用 ArrayBlockingQueue、PriorityQueue 和…

[tpointtech12]

The Ultimate Guide to Java Collection

Java libraries are indispensable tools that streamline development by providing pre-written code for common tasks. "The Ultimate Guide to Java Libraries" explores a myriad of libraries that enhance Java programming, from handling data structures to implementing complex algorithms.

A key feature covered is collections in Java, which offer efficient ways to manage groups of objects, improving code efficiency and readability.

TpointTech is a valuable resource for developers seeking in-depth tutorials and examples on using these libraries effectively. Leveraging these libraries can significantly reduce development time and improve application performance.

Overview of Java Collections

The Java Collections Framework includes interfaces, implementations, and algorithms. The core interfaces include Collection, List, Set, Queue, and Map, each serving different purposes.

Collection Interface: 

The root interface of the framework, representing a group of objects known as elements. It is extended by List, Set, and Queue interfaces.

List Interface: 

An ordered collection that allows duplicate elements. Common implementations are ArrayList, LinkedList, and Vector. Lists are ideal when you need to access elements by their index.

ArrayList: Resizable array implementation, offering constant-time positional access but slower for insertion and deletion.

LinkedList: Doubly-linked list implementation, providing efficient insertion and deletion but slower access time.

Vector: Synchronized version of ArrayList, rarely used due to performance overhead.

Set Interface: 

A collection that does not allow duplicate elements. It models mathematical sets and provides implementations like HashSet, LinkedHashSet, and TreeSet.

HashSet: Uses a hash table for storage, offering constant-time performance for basic operations.

LinkedHashSet: Maintains insertion order, slightly slower than HashSet.

TreeSet: Implements the SortedSet interface, ensuring elements are in ascending order, based on their natural ordering or a specified comparator.

Queue Interface: 

Designed for holding elements prior to processing, typically ordered in a FIFO (first-in-first-out) manner. Common implementations include LinkedList, PriorityQueue, and ArrayDeque.

PriorityQueue: Elements are ordered according to their natural ordering or a provided comparator, useful for creating priority-based tasks.

ArrayDeque: Resizable-array implementation of the Deque interface, providing efficient insertion and deletion from both ends.

Map Interface: 

Represents a collection of key-value pairs, where each key maps to one value. Popular implementations are HashMap, LinkedHashMap, and TreeMap.

HashMap: Provides constant-time performance for basic operations, assuming a good hash function.

LinkedHashMap: Maintains a doubly-linked list of its entries, preserving the order of insertion.

TreeMap: Implements the SortedMap interface, ensuring keys are in ascending order.

Advantages of Java Collections Framework

Reduces Programming Effort: With a set of ready-made data structures and algorithms, JCF eliminates the need for developers to implement complex data structures from scratch.

Increases Program Speed and Quality: Standardized interfaces and optimized implementations ensure high performance and reliability.

Interoperability: Collections can be easily passed across APIs, reducing the complexity of integration.

Ease of Maintenance: Well-documented and widely-used classes make it easier for developers to maintain and enhance code.

Common Algorithms in JCF

Java Collections Framework includes various algorithms to perform routine tasks, such as sorting, searching, and shuffling. These algorithms are static methods in the Collections utility class.

Sorting: Collections.sort(List list), sorts the specified list into ascending order.

Shuffling: Collections.shuffle(List list), randomly permutes the elements in the list.

Searching: Collections.binarySearch(List> list, T key), performs binary search on a sorted list.

Conclusion

The Java Collections Framework is indispensable for any Java developer. It offers a standardized and efficient way to manage groups of objects, making code more robust and maintainable.

By leveraging the various interfaces and implementations, such as lists, sets, queues, and maps, developers can handle data structures effectively.

Understanding collections in Java, as detailed on resources like TpointTech, is crucial for building high-performance applications. Whether you're a beginner or an experienced developer, mastering Java collections will significantly enhance your programming capabilities.

[myprogrammingsolver]

Vertex Distance Data Structure

In the Graph class and Dijkstra’s algorithm, you will be using the VertexDistance class implementation that we have provided. In the Graph class, this data structure is used by the adjacency list to represent which vertices a vertex is connected to. In Dijkstra’s algorithm, you should use this data structure along with a PriorityQueue. At any stage throughout the algorithm, the PriorityQueue of…

[full-stack-development21]

Unraveling the Power of Java Collections Framework and Interfaces

In the realm of Java programming, understanding the intricacies of the Java Collections Framework and Interfaces is pivotal for building robust and efficient applications. Let's delve into the essentials, including Java PriorityQueue and sets in Java, to harness the full potential of these foundational components.

Java Collections Framework: A Comprehensive Toolbox

The Java Collections Framework is a powerhouse of data structures and algorithms, offering a versatile toolbox for developers. It provides interfaces and classes for managing and manipulating groups of objects, ensuring flexibility and efficiency in Java programming.

Java Interfaces: Enabling Polymorphism and Abstraction

Java Interfaces play a crucial role in achieving polymorphism and abstraction in programming. By defining a set of methods that implementing classes must adhere to, interfaces allow developers to create flexible and interchangeable components within their codebase.

Java PriorityQueue: Prioritizing Efficiency

Java PriorityQueue, a class within the Collections Framework, stands out as a specialized queue implementation. It orders elements based on their natural ordering or according to a specified comparator, enabling developers to prioritize and efficiently manage tasks in their applications.

Sets in Java: Uniqueness and Order

Sets in Java, a part of the Collections Framework, ensure uniqueness of elements within a collection. Whether using HashSet, TreeSet, or LinkedHashSet, developers can leverage sets to manage distinct elements and, in some cases, maintain a specific order.

Conclusion: Elevating Java Programming Proficiency

Mastering the Java Collections Framework, Java Interfaces, PriorityQueue, and sets in Java empowers developers to create scalable and well-organized applications. These foundational concepts not only streamline data management but also enhance the overall efficiency and maintainability of Java code. As you explore these elements, you unlock the potential to elevate your proficiency in Java programming, creating more robust and sophisticated software solutions.

[c-official]

So here is a problem:

You are given an array of n integers. A move consists of increasing or decreasing a number in your array by 1. What is the minimum number of moves needed to get the array to be increasing(not strictly)?

Here is some pseudocode for a solution:

// you are given the array `nums`

PriorityQueue p_queue

Number ans

for val in nums {

p_queue.push(val)

p_queue.push(val)

ans += p_queue.pop()-val

}

return ans

//

And the question now is, how does that work?

Hey idiot /nm what's fucking

Hell yeah. You know what fucks? Slope trick.

[fortunatelycoldengineer]

BFS . . . . for more information http://bit.ly/3TLpfGJ check the above link

[volodimirg]

PriorityQueue дозволяє реалізувати чергу на основі пріоритету. Така черга може бути корисна, наприклад, у разі необхідності обслуговування клієнтів згідно пріоритету. 

[learn4master-blog]

Find median of a infinite stream of integers

Find median of a infinite stream of integers

Median of a stream of numbers Given a stream of integers, find the median of the stream of numbers received so far.  Median is the middle value in an ordered integer list. If the size of the list is even, there is no middle value. So the median is the mean of the two middle value. Median of stream of numbers can be queried at multiple times at different point of time. Insertion and median…

[gigglyzero]

2b2t history, by its wiki

2010

Player Count: 50-70 (Accounts vary)

Nothing is much known about the early days of 2b2t, except that the server began in December of 2010. Some that do claim to have joined during this time say that there was nothing spectacular on the server, and that by then, spawn was already a mess.

2011

Player Count: 50-70

During 2011, a lot of things happened. The largest one being the formation of the Facepunch Republic. 2011 is also when many now famous oldfags joined, like Offtopia, xcc2 and popbob.

Early 2011 - Hausemaster teleports to random players to see the progress of his server. Sometimes he would give random items.

April 2011 - Facepunch Republic begins, 4channers take notice of this and tries to stop them.

May 2011 - Player data corruption and change of world generation, causes spawn to look weird.

July 2011 - First post of the 2b2t Comic by Judge Holden

December 2011 - January 2012 - 2b2t gets backdoored by popbob and co.

2011 - The first dupe on 2b2t, the Piston Dupe, was discovered by someone in Facepunch. This involved pushing the piston real fast to duplicate items.

2012

Player Count: 20-50

This year marked one of the most barren times on the server. The server faced drastic player loss during this time due to several facepunchers leaving, the IP changing, and the server being down for three months, causing players to believe that the server shut down for good.

February 2012 - Facepunch Republic ends

February 2012 - Judge's group base at -1 million -1 million is griefed by x0XP.

April 2012 - ImperatorTerrae finds Viking base and 'reforms' it.

June 2012 - 2k2k is founded by the Zion project

2b2t is shut down for three months and changes the IP address from 2b2t.net to 2b2t.org

2013

Player Count: 10-30

2013 is mostly painted by Valkyria, as most other groups of this time period are all but forgotten

February 2013 - Hitlerwood is founded by Coldwave, Zach3397 and Hinderjd

March 2013 - Anatolia is founded by Sato86, Drewbookman and PyroByte

April 2013 - Valkyria is founded by the members of Hitlerwood and Anatolia (Black Flag Group)

May 2013 - 1.4.7 Dupe, The End Dragon is slain

(Unknown month) 2013, Construction of HardHat's Pyramid has started.

June 2013 - 1st Incursion, IGN video (does not generate hype)

August - October 2013 - 2nd Incursion

October/November 2013 - Shenandoah is founded by jesse_number6

December 2013 - 2b2t gets backdoored, Pyrobyte and iTristan have reached the World Border

2014

Player Count: 30-20

During 2014, Valkyria had broken up into a few smaller groups. These include Gape group and the Legion of Shenandoah

January 2014 - Asgard is abandoned after being griefed by popbob during construction

May 2014 - 2k2k is buried in lavacasts and many ancient bases are annihilated by Withers (Including the NFE and Plugin Town)

June 2014 - Legion of Shenandoah begins and Gape 1 is founded

July 2014 - Infamous message shows up on the server website stating that Hausemaster has left the server forever, leaving it in the care of "an anonymous friend." The owner's personality changes immediately after this post.

September 2014 - Fenrir Project begins

October 2014 - Nova is founded in 3b3t

December 2014 - Southern Canal Project is started by ThebesAndSound

2015

Player Count: 20-40

A large population boost happened during this year, mostly from the numerous articles and a massive Reddit post.

January 2015 - 2b2t is updated to 1.8

February 2015 - Fenrir Project ends

March 2015 - Asgard II is founded

April 2015 - Asgard II is destroyed, the 3rd Incursion begins

May 2015

June 2015

August 2015

October 2015

December 2015

Aureus is founded

3rd Incursion ends

Wrath constructed

Kings Landing is founded

The last Facepunch thread closes

Vortex Coalition founded

Project Vault, (now known is the 2b2t museum), is a project determined to keep every single monument in 2b2t untouched and left as a museum to other players, begins.

Motherboard Article is released

VICE mini incursion begins and ends

Imperator's Base is destroyed by Jared2013. Around this time, the server website shuts down.

2016

Player Count: 10-250

This is when 2b2t was most densely populated. This was caused when TheCampingRusher made a video and posted it onto Youtube

February 2016

March 2016

April 2016

RPS Article released

BedTP Exploit surfaces

Space Valkyria destroyed by the Tyranny

KGB destroyed by the Tyranny

Land of Norphs destroyed by the Tyranny

May 2016

June 2016

July 2016

August 2016

September 2016

October 2016

The player count has plummeted, sometimes as low as 1-5 players online.

June 1st - Rusher begins his series on 2b2t. In the coming days, 2b2t becomes flooded with his fans.

June 4th - Rusher declares war on "OGs," a reference to players who have been on the server longer than him.

June 13th - Fit becomes "leader" of Team Veteran, which is supposedly meant to contain the rusher onslaught and preserve the server's pre-rusher culture. This, of course, is debunked later.

June - A lava wall is made around the 500x500 area of spawn, in hopes of keeping Rushers trapped in spawn; this project fails. A very similar project occurs during the 6th Incursion, but fails aswell.

June 17th - Omega City Founded

July 24th - The Fourth Incursion begins with the Veterans raiding Napkin0fTruth's base.

July 28th - 2nd largest battle in 2b2t history (19 players)

July 31st - Aureus is destroyed by the base members themselves.

July - Hardware upgrade, temporary map

The Queue is set up around this time.

August 5th - Fit versus Rusher duel, Fit wins by having more golden apples.

August 19th - Torogadude gets stripped of his priority queue.

September 16th - Largest Battle in 2b2t History: Team Veteran allies with CorruptedUnicorn to take down Rusher. The battle ends in a draw, and Rusher is able to escape.

September 19th - Rusher leaves 2b2t for the first time for about a month.

September 22th - Valley of Wheat destroyed

September - 4th Incursion ends, Newsweek Article released

October 9th - The Rusher War ends. The Veterans say that about 10,400 Rushers had been killed, but this number is frequently questioned.

October 15th -TheCampingRusher returns and makes 3 more videos on 2b2t before he leaves.

October 22nd - Rusher leaves and The Rusher War officially ends. A small presence of rushers/newfags remain, and the server has been radically changed.

October - Offtopia's Drain is destroyed after FitMC made a tour of his base.

November 2016

December 2016

November 11th - 11/11 Dupe leaked to public

November 22nd - Jonathan5454 starts 6Garden. Major construction started sometime in January 2017.

November 25th - AgentGB makes a video on 2b2t. However, he does not make a video afterwards, and states that 2b2t won't be a series.

November 28th - The Fifth Incursion is organized by jared2013, however this fails, and barely makes any attention, and now recognized as a meme.

New coord exploit. Fitlantis is found.

Large battle in Fitlantis

2b2t is updated to 1.11, ending the 11/11 Dupe

AntVenom considers making a video on the history of 2b2t. He asks for the consent of the playerbase and the "admins".

Byrnsy begins his journey to the 2b2t World Border, with hopes of completing the +x Nether Highway. The Nether Highway Expedition group is formed.

The Emperium is founded by TheDark_Emperor.

Player count drops to the low 50s before Fit starts making his videos.

2017

Player Count: 80-200 (50-100 during Temp Maps)

This year saw massive decay of the rusher population and numerous other things

January 2017

February 2017

March 2017

April 2017

May 2017

June 2017

July 2017

August 2017

September 2017

January 1st - Fit returns to 2b2t, with new jewtuber, kid friendly content (starting with minecraft world records by boat). The impact from this has kept the 2b2t playerbase in its 200s, as many players join from Fit each day.

Construction of Block Game Mecca starts

Mid January - Spawn Masons are founded

Late January - The Vortex Coalition gets "disbanded".

HermeticLock's Spawn Base is constructed and The Third Largest Battle of 2b2t History occurs there. The base was constantly rebuilt and lavacasted over and over

15 milliontown is built by the nether highway group

Highland is founded by The_Grand_Lotus

Toro's Theater begins construction

2b2t logo rebranded

Kinorana hacks all maps in 2b2t. Protests against Kinorana begin.

SpawnMasons founded by Hermeticlock.

Early March - The 4th Reich is disbanded

March 3th - Maps are reset and old maps are deleted off 2b2t. The deathspam protest takes a short ceasefire.

March 15th - The Donkey Dupe is leaked to public.

March 18th - The Donkey Dupe has been patched.

March 21st - Wintermelon is griefed

March 22nd - fr1kin discovers an exploit that can bring the server below 1tps. This had normal attention until Fit claims that the lag could crash the server.

March 26th - World Border reached legitimately through the +X Highway. The +X Highway has been completed. Point Nemo is founded.

March 29th - Point Nemo is griefed

March - A player by the name of PriorityQueue is seen at spawn floating and not taking any damage, it was initially thought that he backdoored the server, however this was later proved to be incorrect (possibly the usage of MineChat).

April 1st - 2017 April fools map. This lasted a few days. The queue was also disabled during the uptime of the map

April 9th - Apocalypse Exploit patched, /kill temporarily disabled

April 13th - 24th - Fit's journey to the World Border

May 18th - Fit visits Point Dory without the permission of its builders.

May 20th - Point Dory is griefed

May 25th - Torogadude leaks the coordinates of his own theater by accident. It got destroyed almost instantly.

June 1st - 1st Anniversary of Rusher's Invasion in 2b2t. 2b2t is flooded with lag machines and various shitposts to celebrate the anniversary.

June 4th - Battle between Spawn Masons and Peacekeepers starts.

June 9th - The +Z Highway is completed to the world border.

June 18th - Omega City is destroyed.

June 23rd - The first server crash

June 29th - HermeticLock announced the "second season" of hanging around at his spawnbase

July 6th - The second server crash

July 6th - 7th - Server shut down, as a preparation for the 1.12 update and the addition of new plugins

July 8th- 22th - 1.12 tempmap

July 23th - The original map returns. The owner announces the deletion of all non-vanilla items. However, he accidentally deleted Axe enchantments, player heads, efficiency on shears, and all dungeon spawners. The 1.12 dupe (also known as the 7/21 dupe), was also discovered, which involved spamming in the crafting book

July 24th - Dupe patched sometime around 10:00 AM (EST).

July 28th - Summermelon griefed by Fit and his crew.

July 29th - Fit is exposed by Offtopia in the 2b2t Subreddit for making stuff up just to get a reason to grief Summermelon. The real reason might have involved his youtube career to get money. Fit does this again in 2018 at offtopia's base, Viper.

August 1st - Server restarted by the owner twice at 12:00 AM August 1st (EST)

August 2nd - The 3rd Major crash causes 2b2t down for a while. (Most likely low tps)

August 4th - Jared2013 obtains bureaucrat permissions through Niftyrobo on the 2b2t wiki, and destroys the wiki.

August 5th - Armorsmith lags the server down to 1tps. Causing the playercount to drop to 50-80 players. Queue virtualy dosen't exist.

August 6th - Riot on the wiki and subreddit to demote jared2013 and niftyrobo for the removal of pages with newfag history and several newfag bases such as 6Garden.

August 7th - Wiki is restored and Jared2013 and Niftyrobo has been banned globally from entering FANDOM Wikia itself. The subreddit explodes with wiki rants due to the new admin team consisting of newfags. The new founder, DarkAnhilator, has gathered a source team, and the subreddit calms down.

September 15th - A Spanish YouTuber, ElRichMC makes a video on the server, causing his fans to join and spam the chat in Spanish. Despite the video being quite popular, ElRichMC decides not to make another video and the server returns to normal in a matter of a few weeks.

Mid September - Project Obsidian Sky is completed. The 500x500 region of spawn now has an obsidian roof at Y256. (Today in Mid 2018, most of the obsidian has been destroyed by withers).

Late September - Elytras are disabled due to large amounts of chunks being loaded in a short amount of time, causing both lag and the server file size to grow much too quickly. Elytras have been disabled for almost an entire year. The SOON™ meme appears all over the subreddit because of this.

October 2017

November 2017

December 2017

October 13th - The owner announces removal of pre - June 1st queue.

October 13th - 20th - Bots fill the server in a vain attempt to kill it off, Drachenstein buys oldfags 2 months of priority

November 19th - 20th A redditor named PM_ME_YOUR_TITS_GIRL posted a render of 2b2t on r/gaming and r/minecraft

December 19th - Construction on the Cerulean Islands begins

December 20th - Astral Order is founded after the Purge of Eden

December 21st - VoCo declares the "Vo-Perium" war

December 23rd - X- Digger Team reaches the world border.

December 25th - Armorsmith and Co. planned to lag the server to 0 tps, and succeded to get it down to 0.5 before the owner personally destroyed the machine.

2018

Player Count: 100-250

This year is most known for two incursions (6th and 7th) and the grief of the BGM

January 2018

February 2018

March 2018

April 2018

May 2018

January 1st - Team Inferno reforms into Infrared after all the insiding and griefing

January 10th - United Group Embassy is formed, an initial 15 groups joining.

January 11th - "Vo-Perium" concludes after very little ground is gained. Emperium and VoCo work on building positive relations.

February 4th - Offtopia's Viper Base griefed, led by Fit. Several more subreddit rants occur from this.

February 7th - The 2b2t Media Archive is founded by xyzvp

February 9th - Up to 17 U.G.E. representatives arrive at spawn and begin renovating.

February 13th - 16 U.G.E. representatives fight 4 members of Infrared and Highland at spawn. Renovations continue.

March 20th - Temp map begins while the main map is being transferred from a 4 Terabyte HDD to a 6 TB SSD[1], as it was rapidly approaching the upper size limit of its current hardware. Server traffic is lower than usual but still high. TPS range is around 10 to 13.

March 27th - Main map back up

March 28th - Severe rubberband and lag occours at high TPS as well as several plugins being removed temporarily which allowed for people to use "illegal items" for a short amount of time, as well as being able to use the nether roof while taking heavy amounts of damage.

March 31th - April 2nd - An unnamed April Fools' tempmap starts on March 31st, 2018, and ends April 2nd, 2018. During this period, AntVenom confirms he will be releasing his video on April 3rd. The Sixth Incursion is declared by Sato and the ender dragon on the temp map is killed by the new incursion.

April 2nd - 6th - 2nd tempmap after failure of reverting back the world.

April 3rd - The highly anticipated "Face of Minecraft Anarchy" video is released by AntVenom. New players flood the server. Total player counts reach about 350 at the most.

April 6th - The main map, with very bad timing, comes back online[1] and the owner adds AAC to the server, which causes frequent disconnects and problems in general.

April 12th - 14 million subscriber YouTuber PopularMMOs is seen logging onto the server and is geared by an unknown player. He is later seen at nether spawn and killed with an end crystal. He claims he is not making a video on the server, however not everyone is convinced.

April 16th - 24th - The Obsidian Wall, a wall surrounding 1000 cubic meters of spawn is constructed and finished by Sixth Incursion members. It is named the largest community project ever completed in server history. To get the obsidian necessary , "gulag" slave camps were set up around spawn and new players were captured and forced to mine enderchests to obtain obsidian. This is the first confirmed time slave labor is used in the server's history to complete a community project.

April 26th - The obsidian wall ends up being a failure due to the fact that players are dedicated enough to spend 7 minutes breaking 2 obsidian blocks. Spawn patrolling became a meme after the incursion members became so self-absorbed after the wall was built. Much of the wall got destroyed however it is still very recognizable in most places.

April 29th - The 2b2t Archaeological Society is founded by /r/ryanfortner3333

May 1st - Jared2013 starts "31Days31Greifs" which causes widespread damage across the server

May 3rd - Sixth Incursion ends and is deemed a success.

May 5th - Construction of Mokuzai Island starts.

May 10th - FitMC reveals secrets about the Age of Tyrrany to the general public.

May 18th - Empire's Edge, Emperium's main base, is leaked to the subreddit by an unknown user and the Emperium quickly removes their belongings and destroys the base before anyone else could.

May 25th - The Builders Haven project is founded by Beardler and managed by Jonathan5454

May 28th - All maps on the server are cleared in an attempt to stop more bases from being griefed in any way they might be. The Map Artists of 2b2t claim responsibility for it and most are understanding.

May 30th - The Boedecken, a large base kept secret for nearly two years, is greifed. FitMC makes base tour shortly after. jared2013 did not claim responsibility for the base's greif.

May 31st -

June 2018

July 2018

August 2018

September 2018

October 2018

November 2018

December 2018

June 1st - One of the largest temp-bases on 2b2t, Purgatory was griefed.

June 1st - 700k Spanish-speaking YouTuber TheDaarickPartner starts a series on 2b2t.

June 1st - Second anniversary of Rusher War.

June 1st - The largest base ever built in the server's history and possibly in SMP Minecraft, Block Game Mecca, is greifed. The base members put the blame on Beardler, one of the members of the base. (The basemates later took this back, claiming that Beardler's account was hacked due to negligence, and Beardler had no intent to leak)

June 4th - 65k YouTuber BenMascott makes a video on the server, goes mostly unnoticed

June 7th - Server reaches 50,000 in-game days

June 10th - Large lag spike that lasts for 3 hours, TPS remains 0.6 for the whole time.

June 16th - Purgatory 2, the largest temp-base on 2b2t, was griefed as a revenge act against Beardlers actions.

June 16th - Beardler quits 2b2t, and Block Game Mecca/Boedecken drama ends.

Mid July - Third Donkey Dupe is discovered

July 24th, 2018 - 2b2t wikia hosted on FANDOM was deleted and moved to Miraheze

Mid August - The servers economy is at a point that anything is worthless, including Hacked Items

August 21st - Infrared disbands for the first time

August 22nd - Builders Haven is greifed and disbanded

September 20th - FuzeIII joins 2b2t and begins a series

September 21st - The Seventh Incursion begins

September 21st - Third Donkey Dupe is patched

Sepetember 27th - FuzeIII declares the foundation of Team Baguette and "War on Team Veteran and the Americans"

October 8th - jared2013 is demoted from head of the incursion due to internal drama.

October 13th - The Seventh Incursion is called off by Henry due to lack of leadership initiative. Drama posts on reddit follow soon after.

October 13th - jared2013 makes a new discord and an Incursion revival initiative to complete original goals of the Incursion.

October 30th - jared2013's Incursion Reloaded revival officially ends a day earlier than initial deadline of the 31st due to an inside attempt on the Emperium. This caused jared's discord to be deleted.

October 31st - A 2b2t halloween party was hosted, only lasting for 4 hours

October - Fit's relevancy is questioned after being kicked out of the Seventh Incursion (see Spawn Incursions)

October - New "banning" method involving max filled books with unicode is discovered. Players are "permanently" banned from the server if they are given a certain amount of these books, which will kick them out of the server due to an overflow in packets registered by the server, unless they e-mail Hausemaster to clear their inventories. The phenomena is known as "book banning".

November 7th - 9th - Beardler returns to 2b2t for 2 days and claims he will return in Mid/Late 2019

November 11th - New book related dupe discovered. Dupe causes lag spikes when performed due to constant chunk reloading.

November 17th - BGM (Block Game Mecca) was found to consist of mostly schematic builds, which put an impact on the bases outlook and originality.

November 23rd - 1.13 is announced for 2b2t coming “soon”

November - The 2b2t Wiki is 2 years old

November - Disbanded Infrared is reformed into Iridium

November 29th - The FuzeIII vs Fit duel occurs, Fit "wins".

November 30th - The 2b2t wiki gains public attention due to FuzeIII mentioning the wiki and the general miraheze discord noticing 2b2t. This wiki achieved a record high on Thursday of 900+ views

December 19th - Queue is glitched and drops to 0, resulting in the server being unable to join

December 23rd - Coordinates for planned Christmas party is leaked, chaos ensues.

December 27th - Iridium is disbanded

December - General lack of major activity due to Queue bugs, connection errors, and lag

December - U.G.E is dissolved after long period of inactivity

2019

Player Count: 100-250

"It's the Current Year!"

January 2019

February 2019

January - Lag and queue issues are getting worse.

January 12th - Infrared is revived.

January 19th - Around 18 Vo-Perium members fight 6 Highland members at spawn, making this the largest battle to unfold since the 6th Incursion

January 26th - Infrared disbands once again

January 30th - The owner changes the server message on the player board, saying "1.13 and temporary map expected in February, 2019, with new server hardware. Elytras planned to be re-added. Death messages and end portals re-added."

January 30th - End portals re-disabled

February 20th - Indonesian YouTuber with 187k subscribers, Kurus, makes a video about 2b2t.

February 23rd - The owner changes server message on the player board, it now says "1.13 expected in late March, Book Duplication now Patched due to update of Waterfall."

February 27th - player bflyza constructs thousands of signs above the nether bedrock ceiling at (0, 0) in the nether. Any player who loads this chunk is immediately disconnected from the server, and instantly disconnects upon rejoining in a way that is functionally similar to being book-banned. Dozens of players are chunk-banned due to the exploit.

[pythonprogrammingsnippets]

python a* basic game pathfinding algorithm for navigation in a 2d array

from queue import PriorityQueue import math # A* pathfinding algorithm # https://pythonprogrammingsnippets.tumblr.com/ def astar(start, goal, terrain_map): frontier = PriorityQueue() frontier.put((0, start)) came_from = {} cost_so_far = {} came_from[start] = None cost_so_far[start] = 0 while not frontier.empty(): current = frontier.get()[1] if current == goal: break for next_tile in get_neighbors(current, terrain_map): new_cost = cost_so_far[current] + get_cost(current, next_tile, terrain_map) if next_tile not in cost_so_far or new_cost < cost_so_far[next_tile]: cost_so_far[next_tile] = new_cost priority = new_cost + heuristic(goal, next_tile) frontier.put((priority, next_tile)) came_from[next_tile] = current return came_from, cost_so_far def heuristic(a, b): return math.sqrt((b[0] - a[0]) ** 2 + (b[1] - a[1]) ** 2) def get_neighbors(tile, terrain_map): neighbors = [] for x in range(tile[0] - 1, tile[0] + 2): for y in range(tile[1] - 1, tile[1] + 2): if x >= 0 and y >= 0 and x < len(terrain_map) and y < len(terrain_map[0]): if (x, y) != tile and terrain_map[x][y] != 2: neighbors.append((x, y)) return neighbors def get_cost(current, next_tile, terrain_map): diagonal = abs(current[0] - next_tile[0]) == 1 and abs(current[1] - next_tile[1]) == 1 cost = terrain_map[next_tile[0]][next_tile[1]] if diagonal: cost *= math.sqrt(2) return cost ## ----------------------- def number_to_ascii_character(number): # # 1 = normal, 2 = wall, 3 = water, 4 = lava, 5 = ice, 6 = swamp if number == 1: return " " elif number == 2: return "-" # wall else: return "?" def show_map(terrain_map, path): for x in range(len(terrain_map)): for y in range(len(terrain_map[0])): if (x, y) in path: # if last position in path, show "X" if (x, y) == path[-1]: print("E", end="") # if first position in path, show "S" elif (x, y) == path[0]: print(" B ", end="") else: print(" x ", end="") else: map_char = number_to_ascii_character(terrain_map[x][y]) print(" " + map_char + " ", end="") print("") print("") print("") ## ----------------------- def main(): terrain_map = [ [1, 2, 2, 1, 1, 1, 1, 2, 1, 1, 1, 2, 1, 1, 1, 2, 2, 2 ], [1, 2, 1, 1, 1, 1, 1, 2, 1, 1, 2, 2, 1, 2, 1, 1, 2, 2 ], [1, 2, 2, 2, 1, 1, 1, 2, 1, 1, 2, 2, 1, 2, 1, 2, 1, 2 ], [1, 2, 1, 2, 1, 2, 1, 1, 1, 1, 2, 2, 1, 1, 1, 1, 2, 1 ], [1, 1, 1, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 2, 2, 1 ], [1, 1, 1, 2, 2, 1, 1, 2, 1, 1, 1, 1, 1, 2, 1, 2, 2, 1 ], [2, 2, 1, 2, 1, 1, 1, 2, 1, 1, 2, 2, 1, 2, 1, 1, 1, 2 ], [1, 1, 1, 2, 1, 2, 2, 1, 1, 1, 2, 1, 1, 2, 1, 2, 2, 2 ], [1, 1, 1, 2, 2, 1, 1, 2, 1, 1, 1, 2, 1, 2, 1, 2, 2, 2 ], [1, 1, 1, 1, 2, 2, 1, 2, 1, 1, 2, 2, 1, 2, 1, 2, 2, 2 ], [1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 2, 1, 1, 1, 1, 2, 2 ], [1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 2, 1, 1, 1, 1, 1, 1, 2 ], [1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 2, 1, 2, 1, 1, 1, 1 ], [1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 2, 1, 2, 2, 1 ], [1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 1, 1, 1, 2, 2, 1 ], [1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 2, 2, 1, 2, 1, 2, 2, 1 ], ] came_from, cost_so_far = astar((0, 0), (9, 9), terrain_map) current = (9, 9) path = [] while current != (0, 0): path.append(current) current = came_from[current] path.reverse() print("Start xy: (0, 0)") print("End xy: (9, 9)") print("-= | Path | =-") print(path) show_map(terrain_map, path) if __name__ == "__main__": main()

output:

Start xy: (0, 0) End xy: (9, 9) -= | Path | =- [(1, 0), (2, 0), (3, 0), (4, 1), (5, 2), (6, 2), (7, 2), (8, 2), (9, 3), (10, 4), (10, 5), (9, 6), (8, 6), (7, 7), (8, 8), (9, 9)] - - - - - - - B - - - - - - - x - - - - - - - - - x - - - - - - x - - - - - x - - - - - - - - x - - - - - - x - - - x - - - - - x - - x - x - - - - - x - - x - E - - - - - - x x - - - - - - - - - - - - - - - - - - - - - - - -

[sanesquaregg]

The Collection Framework in Java

What is a Collection in Java?

Java collection is a single unit of objects. Before the Collections Framework, it had been hard for programmers to write down algorithms that worked for different collections. Java came with many Collection classes and Interfaces, like Vector, Stack, Hashtable, and Array.

In JDK 1.2, Java developers introduced theCollections Framework, an essential framework to help you achieve your data operations.

Why Do We Need Them?

Reduces programming effort & effort to study and use new APIs

Increases program speed and quality

Allows interoperability among unrelated APIs

Reduces effort to design new APIs

Fosters software reuse

Methods Present in the Collection Interface

NoMethodDescription1Public boolean add(E e)To insert an object in this collection.2Public boolean remove(Object element)To delete an element from the collection.3Default boolean removeIf(Predicate filter)For deleting all the elements of the collection that satisfy the specified predicate.4Public boolean retainAll(Collection c)For deleting all the elements of invoking collection except the specified collection.5Public int size()This return the total number of elements.6Publicvoid clear()This removes the total number of elements.7Publicboolean contains(Object element)It is used to search an element.8PublicIterator iterator()It returns an iterator.9PublicObject[] toArray()It converts collection into array.

Collection Framework Hierarchy

List Interface

This is the child interface of the collectioninterface. It is purely for lists of data, so we can store the ordered lists of the objects. It also allows duplicates to be stored. Many classes implement this list interface, including ArrayList, Vector, Stack, and others.

Array List

It is a class present in java. util package.

It uses a dynamic array for storing the element.

It is an array that has no size limit.

We can add or remove elements easily.

Linked List

The LinkedList class uses a doubly LinkedList to store elements. i.e., the user can add data at the initial position as well as the last position.

It allows Null insertion.

If we’d wish to perform an Insertion /Deletion operation LinkedList is preferred.

Used to implement Stacks and Queues.

Vector

Every method is synchronized.

The vector object is Thread safe.

At a time, one thread can operate on the Vector object.

Performance is low because Threads need to wait.

Stack

It is the child class of Vector.

It is based on LIFO (Last In First Out) i.e., the Element inserted in last will come first.

Queue

A queue interface, as its name suggests, upholds the FIFO (First In First Out) order much like a conventional queue line. All of the elements where the order of the elements matters will be stored in this interface. For instance, the tickets are always offered on a first-come, first-serve basis whenever we attempt to book one. As a result, the ticket is awarded to the requester who enters the queue first. There are many classes, including ArrayDeque, PriorityQueue, and others. Any of these subclasses can be used to create a queue object because they all implement the queue.

Dequeue

The queue data structure has only a very tiny modification in this case. The data structure deque, commonly referred to as a double-ended queue, allows us to add and delete pieces from both ends of the queue. ArrayDeque, which implements this interface. We can create a deque object using this class because it implements the Deque interface.

Set Interface

A set is an unordered collection of objects where it is impossible to hold duplicate values. When we want to keep unique objects and prevent object duplication, we utilize this collection. Numerous classes, including HashSet, TreeSet, LinkedHashSet, etc. implement this set interface. We can instantiate a set object with any of these subclasses because they all implement the set.

LinkedHashSet

The LinkedHashSet class extends the HashSet class.

Insertion order is preserved.

Duplicates aren’t allowed.

LinkedHashSet is non synchronized.

LinkedHashSet is the same as the HashSet except the above two differences are present.

HashSet

HashSet stores the elements by using the mechanism of Hashing.

It contains unique elements only.

This HashSet allows null values.

It doesn’t maintain insertion order. It inserted elements according to their hashcode.

It is the best approach for the search operation.

Sorted Set

The set interface and this interface are extremely similar. The only distinction is that this interface provides additional methods for maintaining the elements' order. The interface for handling data that needs to be sorted, which extends the set interface, is called the sorted set interface. TreeSet is the class that complies with this interface. This class can be used to create a SortedSet object because it implements the SortedSet interface.

TreeSet

Java TreeSet class implements the Set interface it uses a tree structure to store elements.

It contains Unique Elements.

TreeSet class access and retrieval time are quick.

It doesn’t allow null elements.

It maintains Ascending Order.

Map Interface

It is a part of the collection framework but does not implement a collection interface. A map stores the values based on the key and value Pair. Because one key cannot have numerous mappings, this interface does not support duplicate keys. In short, The key must be unique while duplicated values are allowed. The map interface is implemented by using HashMap, LinkedHashMap, and HashTable.

HashMap

Map Interface is implemented by HashMap.

HashMap stores the elements using a mechanism called Hashing.

It contains the values based on the key-value pair.

It has a unique key.

It can store a Null key and Multiple null values.

Insertion order isn’t maintained and it is based on the hash code of the keys.

HashMap is Non-Synchronized.

How to create HashMap.

LinkedHashMap

The basic data structure of LinkedHashMap is a combination of LinkedList and Hashtable.

LinkedHashMap is the same as HashMap except above difference.

HashTable

A Hashtable is an array of lists. Each list is familiar as a bucket.

A hashtable contains values based on key-value pairs.

It contains unique elements only.

The hashtable class doesn’t allow a null key as well as a value otherwise it will throw NullPointerException.

Every method is synchronized. i.e At a time one thread is allowed and the other threads are on a wait.

Performance is poor as compared to HashMap.

This blog illustrates the interfaces and classes of the java collection framework. Which is useful for java developers while writing efficient codes. This blog is intended to help you understand the concept better.

At Sanesquare Technologies, we provide end-to-end solutions for Development Services. If you have any doubts regarding java concepts and other technical topics, feel free to contact us.