Designing the Data Schema A Poll model stores the main poll questions. id: Primary key, auto-incrementing. poll_text: The question text, stored as a CharField with a maximum length of 120 characters. created_at: The creation timestamp, stored as a DateTimeField. An Option model stores the choices as...
Consider the following code: #include <stdio.h> #include <list> #include <set> #include <algorithm> using namespace std; template <class S> void ls(S *s) { typename S::iterator it; it = s->begin(); printf("{ "); while (it!=s->end()) { int n= *it; printf(...
Data Structures Mo's Algorithm Standard Mo's Algorithm Used to solve problems like P1494 [National Training Team] Little Z's Socks. #include <bits/stdc++.h> #define int long long using namespace std; const int MAXN = 200010; struct Query { int l, r, idx; }; struct Fraction { int numerator, den...
Runtime Polymorphism with Abstract Base Classes Defining an abstract base class allows for a unified interface across diverse derived types. The following hierarchy demonstrates a content management system where different media types share common behaviors but implement them uniquely. Media Hierarch...
Non-Type Template Parameters Template parameters are categorized into type parameters and non-type parameters. A type parameter is preceded by class or typename in the template list, while a non-type parameter is a compile-time constant that functions as a parameter for class or function templates a...
Django templates serve as dynamic HTML documents, enabling the insertion of contextual data directly into the frontend. Rather than constructing HTML strings within view functions, templates allow developers to separate presentation logic from business logic. This approach significantly enhances cod...
Generic Programming Consider an example: How to implement a generic swap function? In C++, function overloading allows us to use the same function name for different types. For example: void Exchange(int& a, int& b) { int temp = a; a = b; b = temp; } void Exchange(double& a, double&...
Jinja2 Template Engine FastAPI, as a Python web framework, does not include a built-in HTML template engine. This flexibility allows developers to use any template engine, with Jinja2 being the officially recommended choice. pip install jinja2 Basic Setup from fastapi import FastAPI, Request from fa...