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Rajan Kumar

Founder at HackersFriend

India

Python, HTML, CSS, Django, JavaScript, Competitive programming

https://www.hackersfriend.com

HackersFriend @rajan ( Joined 6 years, 8 months ago )


Bio: Rajan is Founder of HackersFriend.




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rajan published an article

Dec. 19, 2020 ⋅ 39539 views


How to install Python libraries without using the pip command ?


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rajan published an article

May 9, 2022 ⋅ 3227 views


Leaky Bucket algorithm for Rate limiting system design


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rajan published an article

July 18, 2021 ⋅ 2401 views


What is HTTP header X-Forwarded-Host ?


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rajan published an article

April 16, 2020 ⋅ 3228 views


How does django prevents clickjacking ?


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rajan published an article

July 10, 2022 ⋅ 2693 views


How to present your software engineering projects


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rajan published an article

Aug. 2, 2020 ⋅ 2252 views


7 Data Science project ideas you can work on to stand out


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rajan published an article

July 9, 2022 ⋅ 2091 views


Most common mistakes you should avoid in interviews


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rajan published an article

Jan. 20, 2023 ⋅ 2806 views


Python - check if a path is file or directory


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rajan published an article

April 17, 2020 ⋅ 3079 views


Building a simple To Do list app using HTML CSS Javascript


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rajan published an article

March 27, 2020 ⋅ 2700 views


Python - Text to Speech by using pyttsx3


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rajan published an article

Aug. 10, 2020 ⋅ 2010 views


Google off campus drive 2020 for India location


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rajan published an article

April 3, 2020 ⋅ 7313 views


How to upload file to SQL server using pyodbc python


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rajan published an article

April 18, 2020 ⋅ 2418 views


Using advanced Python concepts the easy way ( List comprehensions and Slicing )


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rajan published an article

Aug. 12, 2020 ⋅ 2215 views


How to separate Django application config files from code using python decouple


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rajan published an article

Sept. 4, 2020 ⋅ 3872 views


5 Best Books for Competitive Programming


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rajan published an article

July 10, 2023 ⋅ 3049 views


Designing DB schema for efficient pagination


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rajan published an article

Jan. 22, 2023 ⋅ 2232 views


How to get inside docker container shell ?


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rajan published an article

April 20, 2020 ⋅ 2426 views


Advanced python concepts the easy way ( Lambda , Map and Filter )


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rajan published an article

March 27, 2020 ⋅ 3246 views


Building a news headlines player using Python and text to speech


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rajan published an article

Aug. 11, 2020 ⋅ 2941 views


How to return JSON Encoded response from Django View


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rajan published an article

July 4, 2023 (Updated July 4, 2023) ⋅ 2635 views


Embedding agility in software developments


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rajan published an article

Jan. 20, 2023 (Updated Jan. 20, 2023) ⋅ 3215 views


Python - Raise an exception with message


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rajan published an article

April 28, 2022 (Updated April 24, 2022) ⋅ 3346 views


How to format date output in Linux bash script


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rajan published an article

Aug. 30, 2020 (Updated Aug. 30, 2020) ⋅ 2165 views


5 Analytical skills you must acquire as a data scientist


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rajan published an article

July 21, 2020 (Updated July 21, 2020) ⋅ 2014 views


Handling Exceptions in Python


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rajan published an article

May 24, 2020 (Updated May 24, 2020) ⋅ 2426 views


Automating backup of PostgreSQL database


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rajan published an article

May 16, 2020 (Updated May 16, 2020) ⋅ 5258 views


Building Instagram Profile pic downloader in python


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rajan published an article

April 28, 2020 (Updated April 28, 2020) ⋅ 2340 views


Iteration Protocol and Generators in Python


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rajan published an article

April 15, 2020 (Updated April 15, 2020) ⋅ 1777 views


Why python is so popular despite being slow ?


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rajan published an article

April 4, 2020 (Updated April 6, 2020) ⋅ 1699 views


How to redirect using javascript


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rajan published an article

March 29, 2020 (Updated March 30, 2020) ⋅ 3441 views


How to prepare for Hack With Infy 2020


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rajan published an article

March 22, 2020 (Updated March 24, 2020) ⋅ 12123 views


Filtering empty or NULL values in a Django queryset


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rajan published an article

Jan. 25, 2020 (Updated March 9, 2020) ⋅ 1529 views


forEach() Vs map() in JavaScript - Things every developer should know


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rajan published an article

Jan. 23, 2020 (Updated Jan. 16, 2020) ⋅ 1636 views


Convert a number to a string in C - best way


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rajan published an article

Jan. 23, 2020 (Updated Jan. 12, 2020) ⋅ 27708 views


Building news aggregator web app with Django using python web scraping


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rajan published an article

Jan. 23, 2020 (Updated Jan. 8, 2020) ⋅ 1610 views


Find Length of a Linked List


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rajan published an article

Jan. 23, 2020 (Updated Jan. 8, 2020) ⋅ 2620 views


Sort string of characters C++


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rajan published an article

Jan. 23, 2020 (Updated Jan. 8, 2020) ⋅ 1478 views


Print a matrix in spiral form


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rajan published an article

Jan. 23, 2020 (Updated Jan. 6, 2020) ⋅ 1455 views


Print reverse of a string using recursion


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rajan published an article

Jan. 23, 2020 (Updated Jan. 5, 2020) ⋅ 4331 views


Amazon Product Price tracking using Python


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rajan published an article

Jan. 23, 2020 (Updated Jan. 3, 2020) ⋅ 1673 views


Program to find the mid-point of a line


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rajan published an article

Jan. 23, 2020 (Updated Jan. 3, 2020) ⋅ 2031 views


Generate QR Code using python with pyqrcode module


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rajan published an article

Jan. 23, 2020 (Updated Dec. 27, 2019) ⋅ 5908 views


Mouse and keyboard automation using Python


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rajan published an article

Jan. 23, 2020 (Updated Dec. 26, 2019) ⋅ 1261 views


C++ Trigonometric functions


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rajan published an article

Jan. 23, 2020 (Updated Dec. 26, 2019) ⋅ 2127 views


Remove one element to maximize XOR of array


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rajan published an article

Jan. 23, 2020 (Updated Dec. 6, 2019) ⋅ 1313 views


Algorithms and Maths you need to know for hard level competitive programming problems


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rajan published an article

Jan. 23, 2020 (Updated Dec. 2, 2019) ⋅ 1600 views


C++ Hacks for Competitive programming


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rajan published an article

Jan. 23, 2020 (Updated Nov. 21, 2019) ⋅ 2558 views


Add two numbers without using arithmetic operators


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rajan published an article

Jan. 23, 2020 (Updated Nov. 19, 2019) ⋅ 2984 views


Efficient Method to Check if a Number is Multiple of 3


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rajan published an article

Jan. 23, 2020 (Updated Nov. 18, 2019) ⋅ 2026 views


DNA to Protein Converter using Python 3 and Django 2.1


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rajan published an article

Jan. 23, 2020 (Updated Nov. 16, 2019) ⋅ 2174 views


Step by step guide to improve competitive programming skills


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rajan published an article

Jan. 23, 2020 (Updated Nov. 13, 2019) ⋅ 3220 views


Implement a Dictionary using Trie


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rajan published an article

Jan. 23, 2020 (Updated Nov. 9, 2019) ⋅ 1311 views


Range Trees


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rajan published an article

Jan. 23, 2020 (Updated Oct. 19, 2019) ⋅ 9332 views


How to prepare for Google Kickstart – a CodeJam competition?


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rajan published an article

Jan. 23, 2020 (Updated Sept. 28, 2019) ⋅ 1206 views


HackersFriend Graduated from Y Combinator's Startup School


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rajan published an article

Jan. 23, 2020 (Updated Aug. 17, 2019) ⋅ 1366 views


Find maximum occurring character in a string


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rajan published an article

Jan. 23, 2020 (Updated Aug. 16, 2019) ⋅ 3245 views


Sort an array without changing position of negative numbers


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rajan published an article

Jan. 23, 2020 (Updated Aug. 14, 2019) ⋅ 1818 views


What is Binary Search Tree (BST) ?


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rajan published an article

Jan. 23, 2020 (Updated Aug. 13, 2019) ⋅ 1733 views


Merge two Binary search Trees with constant extra space


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rajan published an article

Jan. 23, 2020 (Updated Aug. 2, 2019) ⋅ 6855 views


How to generate OTP (One time password) using python


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rajan published an article

Jan. 23, 2020 (Updated July 25, 2019) ⋅ 3153 views


Get current weather of any city with python using openweathermap API


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rajan published an article

Jan. 23, 2020 (Updated July 25, 2019) ⋅ 4434 views


Getting real time currency exchange rate using Python


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rajan published an article

Jan. 23, 2020 (Updated July 23, 2019) ⋅ 1265 views


Find prime numbers in the first half and second half of an array


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rajan published an article

Jan. 23, 2020 (Updated July 18, 2019) ⋅ 2139 views


Django optimizing Database queries


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rajan published an article

Jan. 23, 2020 (Updated July 16, 2019) ⋅ 6523 views


Check whether two strings contain same characters in same order


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rajan published an article

Jan. 23, 2020 (Updated July 16, 2019) ⋅ 6492 views


Count duplicates in a given linked list


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rajan published an article

Jan. 23, 2020 (Updated July 13, 2019) ⋅ 2462 views


Function Pointers in C++


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rajan published an article

Jan. 23, 2020 (Updated July 12, 2019) ⋅ 4987 views


Remove an element to maximize the GCD of a given array


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rajan published an article

Jan. 23, 2020 (Updated July 9, 2019) ⋅ 8250 views


Find Sum of all Submatrices of a Given Matrix


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rajan published an article

Jan. 23, 2020 (Updated June 6, 2019) ⋅ 1362 views


Length of longest sub-array with maximum arithmetic mean


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rajan published an article

Jan. 23, 2020 (Updated May 29, 2019) ⋅ 1574 views


Learn Full stack development from scratch part - 1 ( step by step guide )


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rajan published an article

Jan. 23, 2020 (Updated Jan. 23, 2019) ⋅ 1693 views


Shuffle elements of an Array most efficient way , Fisher Yates shuffle algorithm


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rajan published an article

Jan. 23, 2020 (Updated Jan. 21, 2019) ⋅ 1240 views


Top 10 jobs that will have high demand in future


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rajan published an article

Jan. 23, 2020 (Updated Jan. 21, 2019) ⋅ 1239 views


Top 5 Tv shows Programmers must watch