Soak Test

Testing random problems One big problem with testing these kind of solutions is that by nature, the problem is random and therefore will be different each time you test it. Unit testing can help – […]


First Generated Puzzle

We had managed to generate a completed puzzle from scratch in the previous section, following the first step of creating a viable solver. The next step is to take the completed puzzle and remove cells from it till […]



Planning Solving according to strategies is pretty straightforward. Generating puzzles is more complex and exercises your comfort with recursion. In general terms generating a puzzle follows these steps Create an empty grid Use brute force […]


Assigning Parents and Children

Recap In the introduction to the Roadmapping project we created a rudimentary procedure and class that read in our data and created the basic structure we will need to produce generalized road-maps from simple tabular data. The next step […]


First Shapes

Recap We’ve read our data, and set up the parameters. The data structures are working according to our debug reports, and we have dipped our toe into recursion. Now to pull it all together and […]


Roadmap Parameters

How to collect parameter data There are many ways to get user input in VBA, including the use of forms and so on. However that is not going to be very good for our purposes, […]


Getting to Grips with recursion

One concept that people always struggle to get their head around is recursion. It really is rather straightforward and elegant but in execution it is always difficult to get right. Even if you include recursion […]


Sorting Collections

Sorting collections is something you might need to do. In this example, we’ll use the cMyClass object we created in Get Started Snippets to demonstrate sorting a collection of objects and how to use recursion to sort the object’s […]

No Picture

How to traverse a treeview

Treeview traversal and recursion In Rest Results Explorer i showed how to Create a treeview from json using the treeView control. Objects like the treeview are generally dealt with recursively – see Getting started with recursion and Getting to Grips with recursion for […]


Hiding data in Excel Objects

Why would you want to? If you want to learn about the cJobject and jSon with VBA you may want to start with  How to use cJobject First off I talk about ‘hiding data’. What […]

Excel and SQL

Basic Solver

Strategies The first step is to put together a basic solver. In Sudoku, there are 3 Regions – Row, Column and Box, but you probably know that already if you are reading this. Other terminology […]

Microsoft Office & VBA

Sudoku Generator and Solver

What is this These few pages are about how to create a Sudoku Solver and Generator using Excel/VBA. If you just want one, then go ahead and download it. If you are interested in how to […]

Google API


If you are a ‘recursion newbie’, you may want to first read Getting started with recursion, or take a look at a real, but simple example with How to traverse a treeview Getting to grips with recursion […]


Roadmap Generation

Introduction to roadmapping This section shows how to build a roadmapper. You can of course download the finished project if you don’t want to follow along with the development and just need a ready made one. It’s the […]