Yesterday I have spent some hours, trying to resolve one problem for shortest paths. The problem was coming from HackBulgaria and was somehow similar to these two problems here: Get the shortest path in a weighted graph with Dijkstra Dijkstra for …

Python Algorithms – Full Dijkstra is stunning again Read more »

Today, I will take a look at a problem, similar to the one here. In the article there, I produced a matrix, calculating the cheapest plane tickets between any two airports given. Today, the task is a little different. I would …

Python – Get the shortest path in a weighted graph – Dijkstra Read more »

Just a day ago I have participated at an exam, organized from SoftUni for SQL server. The exam can be found here and the questions for it are here. In the current article I will present my answers from the first part …

SQL Server – Solution of the first part of the SoftUni Exam for SQL Server Read more »

Today I have received something, that at first looked as a spam e-mail, but for some reason the spam filter has not caught it. Then I took a second look at it and I have noticed, that it was from …

Review – 11 incredible Excel conditional Formatting Tricks, Excel Shortcuts, 7 Genius ways of using Advance Filter Read more »

After the article here, concerning the building of the binary trees and their usefulness, today I will show how to use these trees in action 🙂 Imagine that we have the following problem, used in arena.hackbulgaria.com: Implement a program in …

Python – Usage of a Binary Tree with List in Python Read more »

Binary trees are really useful, if you are solving an algorithmic problem. They consists of nodes (a.k.a vertices) and edges. Thus, each node has two edges, which are leading to another node. Something like this: The above tree is a simple random non-balanced …

Python – Build a binary tree list in python Read more »

There is a simple way in VBA and in Python to create tables in the database you need, giving the tables a name of a variable and the type of a variable. In SQL Server, we also have a way …

SQL Server – Create two tables with primary and foreign key with SQL code Read more »

I have started to explain tricks with SQL Server in a series of articles about a week or two ago. Today I will use a database, mentioned in a previous article. Get data below average The task is to get top …

SQL Server – Get data below the avarage; Difference between Left and Right Join Explained Read more »

As I have already started some time ago with SQL Server, in this article I will present the way to write a if-else case in sql query. The database is available here, I have used a sample DB for one …

SQL Server – Conditional Query And Multiple Tables Join (Many to Many Query) Read more »

So, after starting with SQL Server custom views, SQL Server Triggers, SQL Server Procedures and Functions, now it is time to pay some attention to SQL Transaction as well. What are transactions? Microsoft says the following:  A transaction is a single …

SQL Server – Simple Transaction in SQL Server Read more »