Could anyone help me with this? Whenever I try to insert a node into a binary search tree, I could an error. It's a contract violation in the second use case (< num (root-bst bst)). Here's my code: (define empty-bst? (lambda (bst) (null? bst))) (define empty-bst (lambda () '())) (define make-bst ...

I have recently finished my first real C++ program. It is text based, but hey, what d'ya expect out of a student? So, I would like person(s) to review the code I have written. It ain't short, but I wouldn't call it a "long" program either. I couldn't figure if I could attach a file or not, so I p...

Background I've been looking into a few different way to implement error reporting for an embedded system in C and there a couple things that I'd like to incorporate: A generic and extensible error type. Backward compatibility with OK and ERROR returns (i.e. can effectively return 0 or 1). Well ...

I put together some functions that allows a PHP script to send the SQL data obtained from user inputs on a website via an email attachment as a CSV file. It works perfectly and I have no issues with the code. Alternatively with the right SQL query it would run every X amount of days with a cron j...

I am making a program in which it consists of adding, modifying, searching and deleting a user, but I am doing it when I make a record, it saves it in a txt but now that I want to modify, search or delete a data, but what I want to do is search for what I have in my txt to look for a specific dat...

I am reading from bitstring import BitArray a = b'\x00\x01' b = BitArray(a).bin c = [x * 3 for x in b] The problem is with variable c. the a variable normally is very big, which makes the program run about few minutes. The goal is to make every binary number(which normally will be read from the ...

I have a mongodb collection which looks like this: data = [ {number: 1, status: "ERROR", date: "2020-02-02"}, {number: 1, status: "OK", date: "2020-02-03"}, {number: 2, status: "ERROR", date: "2020-03-02"}, {number: 2, status: "OK", date: "2020-03-03"}, {number: 3, status: "OK", date: "2020-04-02"...

Description This is a simple "demo" app designed to help gain familiarity with interacting with an Sqlite database from C#, particularly storing images as blobs. The database has a single table, Contacts, represented by the following table creation SQL: CREATE TABLE "Contacts" ( "id" INTEG...

What more is expected of this question? It's not any less detailed than this one, nor is its answer any more thorough than this. It appears some users expect "more text" that only gives appearance of "more detail" but doesn't add any real substance to the question. The only difference in two link...

I am trying to do multiple queries in one call, so I organized my code as below: try{ $query = $this->conn->begin_transaction(); $query = $this->conn->prepare("INSERT INTO table1(xx, xxx, xxxx, xxxxx, xxxxxx, xxxxxxx, xxxxxxxx, xxxxxxxxx, xxxxxxxxxx, xxxxxxxxxxx, xxxxxxxxxxx) VALUES (?, ?, ?, ?,...

I'm willing to check an an object's values in typescript, based on another object's keys. The mental model is "the key exists, it's not an object, is the value in obj set, otherwise, it's an object, iterate again". What would be your recommandations about this simple snippet : /** * Returns an a...

I have recently started learning Java and decided to make a basic MDAS calculator in Swing. I am not completely new to programming but I may be making some common mistakes, or not writing the most efficient code. I wanted to make a calculator that can take multiple numbers and operations before f...

The prompt is as follows: This script will use a text menu to give the user options. The options will include the ability to add grades of different types as well as an option to print the current grades and average. Types of grades are tests, quizzes, and assignments. For the final average, the ...

As I asked a question here, I want to write a python code for the following problem: A person provides a service and he/she can serve k clients each minute. Now, client number i comes at the beginning of minute a_{i} and waits w_{i} minutes to receive the service and if they don't receive the ser...

I decided to implement a DisjointSet<T> data structure myself in Rust, with no dependencies except for std, for the challenge and to get better at Rust. I wanted to have as few requirements for T as possible, especially not T: Copy. I also wanted to be able to easily iterate over subsets easily. ...

I have the following algorithm which splits DateTime range into multiple ranges based on night time range. For example: Night start: 22:00, Night end: 06:00 Start time: 2020-10-26 21:00:00 End time: 2020-10-27 07:00:00 Expected output: 2020-10-26 21:00:00 - 2020-10-26 22:00:00 2020-10-26 22:00:0...

I'm trying to improve my code, I'm certain that there's a better way of doing this, any help is appreciated The algorithm description is as follows: You are given an array A of N integers and an integer S. Your task is to compute how many ways one can choose a contiguous fragment of A that has an...

I am to preview where a new element will be added on button click. I thought about just creating the element and showing that in the preview, but I have several buttons and some of the elements they create require input (via window.prompt) so I decided to just make a placeholder div and use that ...

I'm working on a spigot plugin, that deals with messages to from players on a server to the admin's. It's the same plugin this question relates to: SQL structure to save coordinates for spigot plugin . I've got a command, which allowes access to the inbox, and does all kinds of operations on the ...

Seeing as a concurrent collection does not exist in .net that allows specific items to be removed, I have put together the following class. It's important to note that it is only threadsafe until the LockTimeout on a given operation expires. The main goal was to to guard against cheeky 'InvalidOp...

I have written Python code which uses multiple if condition and a for loop. The main objective of code is to produce traffic light system based on certain condition. Red = -1 Yellow = 0 Green = 1 It takes 4 months (m0, m1, m2, m3) and dataframe as an input and run the condition through each rows...

I've been thinking about it for a while and, after asking a question on vi.stackexchange, I decided to write a small plugin myself and put it on GitHub; basically it offers a mapping to activate a kind of "window movement" mode where Vim waits for inputs that it appends to Ctrl+w, so that one doe...

Example: echo '<select>'; $mysqli = new mysqli( "localhost", "root", "user", "db" ); $con = $mysqli; if( $mysqli->connect_errno ) { die("Failed to connect to MySQL: (" . $mysqli->connect_errno . ") " . $mysqli->connect_error); } $username = $_SESSION['user']; $selectStatement = "SELECT id FROM pu...

(Someone told me this would fit better on this site than on Stack Overflow so I am reposting.) I tried to implement a singly linked list myself, sorry it is not commented but I think it should be pretty self-explanatory, if not feel free to comment. I know that using namespace std; is not optimal...

I am trying to improved my coding skills. I mainly work in web development. I had a "system" that I use in all my projects to fetch data from my DB to the browser. I tried an implementation of OOP, it works fine, but I dont think I did it correctly. How can I optimized this code to make full use ...

The tag [parse.com] should be replaced with [parse-platform] analogous to a similar renaming that was done on Stack Overflow. This tag request is part of the Parse Community's effort to maintain Parse Platform related tags on Stack Exchange, as described here.