All Hard Articles

Colored Flower by circles using Turtle in Python

Prerequisite: Turtle Programming Basics Turtle is an inbuilt module in Python. It provides drawing using a screen (cardboard) and turtle (pen). To draw something on… Read More

Python-turtle

Python

N-Queen Problem | Local Search using Hill climbing with random neighbour

The N Queen is the problem of placing N chess queens on an N×N chessboard so that no two queens attack each other. For example, the… Read More

chessboard-problems

Arrays

Backtracking

C++

C++ Programs

DSA

Mathematical

Nth angle of a Polygon whose initial angle and per angle increment is given

Given four integers N, A, K, n where N represents the number of sides the polygon, A represents the initial angle of the polygon, K… Read More

Maths

school-programming

DSA

Geometric

Greedy

Mathematical

PostgreSQL – REGEXP_MATCHES Function

The PostgreSQL REGEXP_MATCHES() function is used to match a POSIX regular expression against a string and subsequently returns the strings that match the pattern. Syntax:REGEXP_MATCHES(source_string,… Read More

PostgreSQL-function

PostgreSQL-String-function

PostgreSQL

PostgreSQL – Reset Password For Postgres

In this article, we will look into the step-by-step process of resetting the Postgres user password in case the user forgets it. PostgreSQL uses the… Read More

postgreSQL-administration

PostgreSQL

PostgreSQL – NTH_VALUE Function

In PostgreSQL, the NTH_VALUE() function is used to get a value from the nth row in a result set. Here is the syntax of the… Read More

PostgreSQL-function

PostgreSQL-Window-function

PostgreSQL

Check whether there exists a triplet (i, j, k) such that arr[i] < arr[k] < arr[j] for i < j < k

Given an array arr[], the task is to check that if there exist a triplet (i, j, k) such that arr[i]<arr[k]<arr[j] and i<j<k then print… Read More

cpp-stack

Arrays

DSA

Greedy

Misc

Stack

How to Delete a column from Pandas DataFrame

Deleting data is one of the primary operations when it comes to data analysis. Very often we see that a particular column in the DataFrame… Read More

pandas-dataframe-program

Python pandas-dataFrame

Python-pandas

Python

Minimum Cost using Dijkstra by Modifying Cost of an Edge

Given an undirected weighted graph of N nodes and M edges in the form of a tuple lets say {X, Y, Z} such that there… Read More

Algorithms-Graph Traversals

cpp-priority-queue

Data Structures-Graph

Dijkstra

priority-queue

Advanced Data Structure

Algorithms

DSA

Graph

Queue

Python – Inversion in nested dictionary

Given a nested dictionary, perform inversion of keys, i.e innermost nested becomes outermost and vice-versa. Input : test_dict = {“a” : {“b” : {}}, “d”… Read More

Python dictionary-programs

Python

Python Programs

Filter words from a given Pandas series that contain atleast two vowels

In this article, how we can filter the words from a given series which contain two or more vowels. Here we’ll see two ways in… Read More

Python pandas-series

Python-pandas

Python

Interfaces and Services

Interfaces and Services is a process that generally provides and gives a common technique for each layer to communicate with each other. Standard terminology basically… Read More

Computer Networks

GATE CS

Create Analog Clock using PyQt5 in Python

Prerequisite: Introduction to pyqt-5 A clock or watch is called “analog” when it has moving hands and (usually) hours marked from number 1 to 12… Read More

Python-projects

Python-PyQt

Python

How to send data of HTML form directly to JSON file?

The task is to send data of HTML form directly to JSON file. Approach: We have an HTML form containing several fields such as name,… Read More

HTML-Misc

PHP-Misc

HTML

PHP

PHP Programs

Web Technologies

How to compare password and confirm password inputs using express-validator ?

Registration or Sign Up on any website always requires a confirmed password input and it must be the same as the password. It is basically… Read More

Node.js-Misc

Node.js

Web Technologies

Fluttertoast in Flutter

Fluttertoast is used to create a toast message by writing only one line of code. Below are some steps to create a Fluttertoast in Flutter.… Read More

android

Flutter

Flutter UI-components

Dart

Find any simple cycle in an undirected unweighted Graph

Given an un-directed and unweighted connected graph, find a simple cycle in that graph (if it exists). Simple Cycle: A simple cycle is a cycle… Read More

BFS

DFS

graph-cycle

C++ Programs

Competitive Programming

DSA

Graph

Tree

Minimum cost to empty Array where cost of removing an element is 2^(removed_count) * arr[i]

Given an array arr[], the task is to find the minimum cost to remove all elements from the array where the cost of removing an… Read More

optimization-technique

Advanced Data Structure

Algorithms

Analysis of Algorithms

Arrays

C++ Programs

Competitive Programming

DSA

Greedy

Sorting

Interval Tree using GNU Tree-based container

Consider a situation where we have a set of intervals and we need the following operations to be implemented efficiently: Add an intervalRemove an intervalGiven… Read More

ES6

Intellipaat

QA - Placement Quizzes-Data Interpretation

Red Black Tree

Scala-Arrays

TCS-coding-questions

Advanced Data Structure

C++ Programs

DSA

Tree

Python OpenCV: Object Tracking using Homography

In this article, we are trying to track an object in the video with the image already given in it. We can also track the… Read More

OpenCV

Python-OpenCV

Python