/java-design-patterns

Design patterns implemented in Java

Primary LanguageJavaOtherNOASSERTION

Design Patterns Implemented in Java

Java CI License MIT Lines of Code Coverage Join the chat at https://gitter.im/iluwatar/java-design-patterns

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Introduction

Design patterns are the best, formalized practices a programmer can use to solve common problems when designing an application or system.

Design patterns can speed up the development process by providing tested, proven development paradigms.

Reusing design patterns helps prevent subtle issues that cause major problems, and it also improves code readability for coders and architects who are familiar with the patterns.

Getting Started

This site showcases Java Design Patterns. The solutions have been developed by experienced programmers and architects from the open-source community. The patterns can be browsed by their high-level descriptions or by looking at their source code. The source code examples are well commented and can be thought of as programming tutorials on how to implement a specific pattern. We use the most popular battle-proven open-source Java technologies.

Before you dive into the material, you should be familiar with various Software Design Principles.

All designs should be as simple as possible. You should start with KISS, YAGNI, and Do The Simplest Thing That Could Possibly Work principles. Complexity and patterns should only be introduced when they are needed for practical extensibility.

Once you are familiar with these concepts you can start drilling down into the available design patterns by any of the following approaches:

  • Search for a specific pattern by name. Can't find one? Please report a new pattern here.
  • Using tags such as Performance, Gang of Four or Data access.
  • Using pattern categories, Creational, Behavioral, and others.

Hopefully, you find the object-oriented solutions presented on this site useful in your architectures and have as much fun learning them as we had while developing them.

How to Contribute

If you are willing to contribute to the project you will find the relevant information in our developer wiki. We will help you and answer your questions in the Gitter chatroom.

The Book

The design patterns are now available as an e-book. Find out more about "Open Source Java Design Patterns" here: https://payhip.com/b/kcaF9

The project contributors can get the book for free. Contact the maintainer via Gitter chatroom or email (iluwatar (at) gmail (dot) com ). Send a message that contains your email address, Github username, and a link to an accepted pull request.

License

This project is licensed under the terms of the MIT license.

Contributors

Ilkka Seppälä
Ilkka Seppälä

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Subhrodip Mohanta
Subhrodip Mohanta

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amit1307
amit1307

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Narendra Pathai
Narendra Pathai

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Jeroen Meulemeester
Jeroen Meulemeester

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Joseph McCarthy
Joseph McCarthy

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Thomas
Thomas

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Anurag Agarwal
Anurag Agarwal

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Markus Moser
Markus Moser

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Sabiq Ihab
Sabiq Ihab

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Amit Dixit
Amit Dixit

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Piyush Kailash Chaudhari

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joshzambales
joshzambales

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Kamil Pietruszka
Kamil Pietruszka

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Zafar Khaydarov
Zafar Khaydarov

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Paul Campbell
Paul Campbell

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Argyro Sioziou

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TylerMcConville

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saksham93
saksham93

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nikhilbarar

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Colin But
Colin But

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Ruslan

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Juho Kang

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Dheeraj Mummareddy

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Bernardo Sulzbach

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Aleksandar Dudukovic

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Yusuf Aytaş

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Mihály Kuprivecz

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Stanislav Kapinus

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GVSharma

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Srđan Paunović

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Petros G. Sideris

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Pramod Gupta

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Amarnath Chandana

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Anurag870

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Wes Gilleland

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Harshraj Thakor

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Martin Vandenbussche

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Alexandru Somai

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Artur Mogozov

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anthony
anthony

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Christian Cygnus

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Dima Gubin

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Joshua Jimenez

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Kai Winter

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lbroman

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Przemek

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Prafful Agarwal

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Sanket Panhale

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staillebois
staillebois

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Krisztián Nagy
Krisztián Nagy

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Alexander Ivanov

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Yosfik Alqadri
Yosfik Alqadri

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Agustí Becerra Milà

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Juan Manuel Suárez

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Luigi Cortese
Luigi Cortese

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Katarzyna Rzepecka

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adamski.pro
adamski.pro

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Shengli Bai
Shengli Bai

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Boris
Boris

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Dmitry Avershin

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靳阳
靳阳

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hoangnam2261
hoangnam2261

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Arpit Jain
Arpit Jain

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Jón Ingi Sveinbjörnsson

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Kirill Vlasov
Kirill Vlasov

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Mitchell Irvin
Mitchell Irvin

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Ranjeet
Ranjeet

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PhoenixYip
PhoenixYip

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M Saif Asif
M Saif Asif

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kanwarpreet25
kanwarpreet25

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Leon Mak
Leon Mak

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Per Wramdemark

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Evan Sia Wai Suan
Evan Sia Wai Suan

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AnaghaSasikumar

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Christoffer Hamberg
Christoffer Hamberg

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Dominik Gruntz
Dominik Gruntz

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Hannes
Hannes

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Leo Gutiérrez Ramírez
Leo Gutiérrez Ramírez

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Zhang WH
Zhang WH

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Christopher O'Connell

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George Mavroeidis

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Hemant Bothra

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Kevin Peters
Kevin Peters

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George Aristy

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Mahendran Mookkiah

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Azureyjt
Azureyjt

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gans
gans

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Matt
Matt

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Gopinath Langote
Gopinath Langote

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Hoswey
Hoswey

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Amit Pandey
Amit Pandey

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gwildor28
gwildor28

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田浩

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Stamatis Pitsios

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qza
qza

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Rodolfo Forte

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Ankur Kaushal

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Ovidijus Okinskas

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Robert Kasperczyk

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Tapio Rautonen

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Yuri Orlov

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Varun Upadhyay

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Aditya Pal

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grzesiekkedzior
grzesiekkedzior

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Sivasubramani M
Sivasubramani M

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Sami Airaksinen

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Janne Sinivirta

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Boris-Chengbiao Zhou
Boris-Chengbiao Zhou

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Jacob Hein

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Richard Jones

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Rachel M. Carmena

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Zaerald Denze Lungos

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Lars Kappert

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Mike Liu

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Matt Dolan

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Manan

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Nishant Arora

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Peeyush

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Rakesh

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Wei Seng

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Ashish Trivedi

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洪月阳

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xdvrx1
xdvrx1

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Bethan Palmer

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Toxic Dreamz

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Edy Cu Tjong

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Michał Krzywański

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Stefan Birkner
Stefan Birkner

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Fedor Skvorcov

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samilAyoub
samilAyoub

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Vladislav Golubinov

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Swaraj
Swaraj

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Christoph Flick

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Ascênio
Ascênio

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Domenico Sibilio

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Akash Chandwani
Akash Chandwani

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Pavlo Manannikov

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Eiman
Eiman

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Rocky
Rocky

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Ibrahim ali abdelghany

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Girish Kulkarni

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Omar Karazoun

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Jeff Evans

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Vivek Singh

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siavash

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ruchpeanuts

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warp125
warp125

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KHADIR Tayeb
KHADIR Tayeb

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ignite1771
ignite1771

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Halil Demir

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Rohit Singh

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byoungju94

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Moustafa Farhat

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Martel Richard

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va1m

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Noam Greenshtain

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yonghong Xu

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jinishavora

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Elvys Soares

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zWeBrain
zWeBrain

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余林颖

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Alain

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VR
VR

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JackieNim

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EdisonE3

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Tao

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Juan Manuel Abate

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Xenilo137

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Samuel Souza

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Marlo Henrique

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AndriyPyzh

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karthikbhat13

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Morteza Adigozalpour

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Nagaraj Tantri

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Francesco Scuccimarri

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Conny Hansson

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Muklas Rahmanto

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Vadim
Vadim

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Simran Keshri
Simran Keshri

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JCarlos

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Ali Ghasemi

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Carl Dea

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Mozartus

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Manvi Goel

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Anum Amin

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Reo Uehara

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Fiordy

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Harshal

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Abhinav Vashisth

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Kevin
Kevin

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Shrirang

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interactwithankush
interactwithankush

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CharlieYu

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Leisterbecker

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DragonDreamer

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ShivanshCharak

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HattoriHenzo

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Arnab Sen

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MohanaRao SV

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Yonatan Karp-Rudin

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Oliani
Oliani

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Renjie LIU

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perfect guy
perfect guy

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xyllq999

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Mohamed Bilal

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Karshil sheth

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kongleong86

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Aitor Fidalgo Sánchez

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Victor He
Victor He

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Minh Nguyen

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Victor He
Victor He

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yiichan
yiichan

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Pan Sem
Pan Sem

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zhoumengyks

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you
you

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Thanks
Thanks

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LazyProgrammer
LazyProgrammer

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Mohammed Faizan Ahmed

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Bruno Fernandes

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SammanPali

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Qixiang Chen
Qixiang Chen

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Shourya Manekar

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Alan
Alan

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JanFidor

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Anton Yakutovich

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steph88ss
steph88ss

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Yujan Ranjitkar

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yusha-g
yusha-g

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Robert Volkmann

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Bipin Kumar Chaurasia

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KyleSong30

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u7281975
u7281975

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harshalkhachane
harshalkhachane

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Tejas Singh

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Sudarsan Balaji

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Vaibhav Agrawal

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u7275858
u7275858

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prasad-333

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JurenXu

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murphShaw

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XianWu99
XianWu99

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JoshuaSinglaANU

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Ricardo Ramos

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Farid Zouheir

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Vinícius A. B.
Vinícius A. B.

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Stefanel Stan

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Prince bhati

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WuLang
WuLang

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Hugo Kat

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Shivanagouda Agasimani

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Aparna
Aparna

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Girolamo Giordano

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Chak-C

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Nakul Nambiar

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KarmaTashiCat

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marikattt

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Hashvardhan Parmar

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YongHwan

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Shogo Hida

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Eugene

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Piyush

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Rahul Raj

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Bharath Kalyan S

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Saiteja Reddy

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Enrique Clerici

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Ramil Sayetov

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东方未白
东方未白

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Fredrik Sejr

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akshatarora0013

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Mughees Qasim

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behappyleee

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Ayush Thakur

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Anthony Bosch

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trananso

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Giammaria Biffi

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Saiful Haque

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JabezBrew

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konstantin-goldman
konstantin-goldman

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Tien Nguyen Minh

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Vladimir
Vladimir

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Surjendu
Surjendu

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bakazhou
bakazhou

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Owen Leung

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Stavros Barousis

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Syyed Ibrahim Abdullah

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JiaDi Zhang

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Sanchit Bansal
Sanchit Bansal

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Md Saiful Islam
Md Saiful Islam

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Antonio Addeo

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Allagadda Sai Upendranath
Allagadda Sai Upendranath

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Matheus Braga
Matheus Braga

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Appari Satya Barghav
Appari Satya Barghav

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Marcel Ribeiro-Dantas

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Muhammad Hanif Amrullah

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JackH408

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Shubham
Shubham

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Nishant Jain
Nishant Jain

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Rhitam Chaudhury
Rhitam Chaudhury

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JerryZhao275
JerryZhao275

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Leonardo Lisanti
Leonardo Lisanti

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Yennifer Herrera

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jnniu-n
jnniu-n

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Miguel Angel Perez Garcia
Miguel Angel Perez Garcia

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Suwan Sankaja
Suwan Sankaja

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alok
alok

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Daniel Lisboa
Daniel Lisboa

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Sam Powell
Sam Powell

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João Fernandes
João Fernandes

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Hong Geon-ui
Hong Geon-ui

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Doksanbir
Doksanbir

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Chant3ll3
Chant3ll3

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YongHwan Kwon
YongHwan Kwon

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Jakub Klimek
Jakub Klimek

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believe
believe

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egg0102030405
egg0102030405

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Ved Asole
Ved Asole

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NewMorning
NewMorning

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资深老萌新
资深老萌新

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Seunghwan Jeon
Seunghwan Jeon

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sugavanesh
sugavanesh

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FinnS-F
FinnS-F

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jerryyummy
jerryyummy

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Manoj Chowdary
Manoj Chowdary

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Aditya
Aditya

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nooynayr
nooynayr

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CYBERCRUX2
CYBERCRUX2

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Luis Mateo Hincapié Martinez
Luis Mateo Hincapié Martinez

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guqing
guqing

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Sashir Estela
Sashir Estela

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omahs
omahs

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leif e.
leif e.

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Jun Kang
Jun Kang

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Kishalay Pandey
Kishalay Pandey

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drishtii7
drishtii7

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David Medina Orozco
David Medina Orozco

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Roman Leontev
Roman Leontev

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Riley
Riley

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k1w1dev
k1w1dev

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dev-yugantar
dev-yugantar

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Adelya
Adelya

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gatlanagaprasanna
gatlanagaprasanna

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Avinash Shukla
Avinash Shukla

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Mayank Choudhary
Mayank Choudhary

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romannimets
romannimets

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Joel
Joel

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Walyson Moises
Walyson Moises

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Xcyq
Xcyq

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Ritabrata
Ritabrata

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Trivikram Kamat
Trivikram Kamat

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Vincent Vanghelle

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Antoine Héritier

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QinShower
QinShower

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