The array is already sorted, we can keep two pointers ii and jj, where ii is the slow-runner while jj is the fast-runner. As long as nums[i] = nums[j]nums[i]=nums[j], we increment jj to skip the duplicate.When we encounter nums[j] != nums[i] the duplicate run has ended so we must copy its value to nums[i + 1]nums[i+1]. ii is then incremented and we repeat the same process again until jj reaches the end of array.Time complexity − O(N)Example Live Demousing System; namespace ConsoleApplication{    public class Arrays{       public int RemoveDuplicatesFromSortedArrayAndReturnLength(int[] arr){          int index = 1; ... Read More

Given an array and number k, the problem states that we have to rotate the array k times.If the given number is 3 then the array must be rotated 3 times.Create a function reverse which takes the array, start and end as a parameter.In the 1st step call reverse method from 0 to array length.In the 2nd step call the reverse method from 0 to k-1.In the 3rd step call the reverse method from k+1 to array length.Example Live Demousing System; namespace ConsoleApplication{    public class Arrays{       public void ReverseArrayKTimes(int[] arr, int k){          Reverse(arr, ... Read More

Take two-pointers, low, high. We will use low pointers at the start, and the high pointer will point at the end of the given array.If array [low] =0, then no swapping requiredIf array [low] = 1, then swapping is required. Decrement high pointer once.Time complexity − O(N)Example Live Demousing System; namespace ConsoleApplication{    public class Arrays{       public void SwapZerosOnes(int[] arr){          int low = 0;          int high = arr.Length - 1;          while (low < high){             if (arr[low] == 1){     ... Read More

We need to take three-pointers, low, mid, high. We will use low and mid pointers at the start, and the high pointer will point at the end of the given array.If array [mid] =0, then swap array [mid] with array [low] and increment both pointers once.If array [mid] = 1, then no swapping is required. Increment mid pointer once.If array [mid] = 2, then we swap array [mid] with array [high] and decrement the high pointer once.Time complexity − O(N)Example Live Demousing System; namespace ConsoleApplication{    public class Arrays{       private void Swap(int[] arr, int pos1, int pos2){   ... Read More

Djoser is a simple authentication library for Django. It is used to generate tokens for authentication; this generated token is generated by taking three fields: username, email and password. It only works on POST request, but you can add its frontend.ExampleCreate a Django project and an app. I named them "DjoserExample" and "myapp".Install two packages −pip install djoser pip install djangorestframeworkIn settings.py, add the following lines −INSTALLED_APPS = [ #below every other apps    'myapp',    'rest_framework',    'rest_framework.authtoken',    'djoser' ] # Below template variable REST_FRAMEWORK = {    'DEFAULT_AUTHENTICATION_CLASSES': (       'rest_framework.authentication.TokenAuthentication',    ),   ... Read More

We get to see Social Share buttons on most of the websites. They play an important role in ecommerce or any blogging or affiliate sites. As a web developer, you surely want people to like your website and want them to tell about your site to others on social media.In this article, we will see how to make an automated website share social button.ExampleFirst of all, create a project and an app.Install the django-social-share package −pip install django-social-shareIn settings.py, add django_social_share as an app in project.INSTALLED_APPS += ['django_social_share']In project's urls.py −from django.contrib import admin from django.urls import path, include ... Read More

In this article, we are going to make a Django profiling. It will show a great deal of information like the total number of GET requests, database queries and many other reports for your website on a URL endpoint. It is great in production because you need to keep a check on many things when your site is in production.It is a great resource if you have to deploy a real-world project.ExampleFirst of all, create a project and an app. Do some basic settings and set up the urls.Now, install the djnago-silk package −pip install django-silkIn settings.py, add the following ... Read More

In this article, we will see how to make a table in Django which will render model data. We are not going to use the tag of html. We will use a simple Django table library which provides features to directly show Django model data in a table with pagination feature.ExampleFirst of all, create a project and an app and set up the urls.Install the django_tables2 package −pip install django_tables2In settings.py −INSTALLED_APPS+=["django_tables2"]In models.py, create a simple model for testing −from django.db import models # Create your models here. class Data(models.Model):    Name=models.CharField(max_length=100)    salary = models.CharField(max_length=20)In urls.py, add ... Read More

We sometimes need to generate the QR code of an URL in our website. QR codes are scanned for verification, website login, opening websites and many things like that. In this article, we will see how to implement that. We are going to create a qrgenerator website in Django.ExampleCreate a Django project and an app. Create a media folder at the same level of project and app.Go to settings.py in the project folder and add the app name in INSTALLED_APPS and add this at the bottom −MEDIA_ROOT = os.path.join(BASE_DIR, 'media/') MEDIA_URL = '/media/'Here we set up our media folder where ... Read More

Model history tracking is a feature which tracks the changes in model object, it tracks things like what change you made in it and when you deleted it. It also helps in the recovery of deleted object of model. In this article, we will take an example to see how to track a model object's history in Django.ExampleFirst of all, set up your project, apps, urls and a model.Install the django-simple-history library −pip install django-simple-historyIn settings.py −INSTALLED_APPS+=[" simple_history"] MIDDLEWARE = [    #other middle ware    'simple_history.middleware.HistoryRequestMiddleware', ]Here we added the "simple_history" module as app and a middleware.Here we don't ... Read More