# Category: computer science

## সর্বাধিক ব্যবহৃত দরকারী লিনাক্স ফাংশন

অধ্যায় 1 প্রাথমিক I/O ফাংশন close ফাংশন: খোলা ফাইল বন্ধ করুন creat ফাংশন: একটি ফাইল তৈরি করুন dup ফাংশন: ডুপ্লিকেট ফাইল বর্ণনাকারী dup2 ফাংশন: নির্দিষ্ট স্থানে ফাইল বর্ণনাকারী অনুলিপি করুন fcntl ফাংশন: ফাইলের অবস্থা...

## These functions are the most commonly used useful Linux functions

Chapter 1 Primary I/O Functions close function: close the opened file creat function: create a file dup function: Duplicate file descriptors dup2 function: copy the file descriptor to the specified location fcntl function: change...

## find two divisors of a number, such that the gcd of the sum of those divisors and the number equals 1

Problem statement you are given an array. you have to find two divisors other than 1, (d1,d2) for each element, ai, such that gcd of the sum of those two divisors and the element...

## Created an online whiteboard within 30 minutes! HOW?

What is an online whiteboard?It is an online writing or drawing tool, just like a board that we used to see in classes. We can write, draw anything on it. Online whiteboards can be...

## Find distinct prime factors from 1 to n in O((n+q)logn) (for q Queries)

Problem: Find distinct prime factors of a number. You will be asked q times. Naive approach: Find out distinct prime factors for each query. It’s inefficient for large number of queries. As each query...

## Group by a column in a given tabular data

A tabular data is given, you have to print all the data in group by some column form. Group by columns refers to all the data entries or row with same that particular column value is to be printed togather.

## Drawing points and lines in OpenGL

Drawing something is easy once you understand how OpenGL works. Points and lines are the primitives for any drawing. This article will make you capable of drawing points and lines using OpenGL implemented in C++ (i.e. g++).

## Goroutine: simple implementation

GoLang Program to run a funtion concurrently with main function and to run multiple funtions concurrently

## Visualization of a stereo audio chunk or frame using OpenCV & PyAudio implemented in python

visualization of audio chunk data read from .wav file into seperate stream

## Simple face detection using haar feature-based cascade classifier with OpenCV implemented in python

A simple face detector with OpenCV, python in less than 15 lines of code (excluding comments) using Haar feature-based cascade classifiers