Month: December 2019

To Trie or not to Trie

I am always interested in learning new and refreshing on known algorithms. I looked at a problem in HackerRank which at this time is not relevant. The problem involves looking for sub strings in a string. There are many algorithms that could be used, but as the saying goes, there are many ways to skin a cat, but I always say that one and only one is the best.

I am not going to discuss the some possible approaches to solve the problem in this post. I will take a look at Tries which might be close. Will build a node for the trie, a trie and then will attempt to figure out if by modifying the node and possibly the trie, I can solve the problem. If we are not able to solve the challenge (I do not expect to solve it with a base Trie), will cover a better approach in the next post. Continue reading “To Trie or not to Trie”

Bigger is Greater

I was going to have a different introduction (the regular chit chat) to this post, but based on the article “Malevolent Machine Learning” by Chris Edwards on Communications of the ACM 12/2019 Volume 62 Number 12 I changed my mind. Allow me to explain.

A couple years ago I took a few courses from Coursera. The general topic was big data and machine learning. The course of interest is “Neural Networks and Deep Learning” by Andrew Ng deeplearning.ai. It was very interesting class and I highly recommend it.

I tried locating my notes on those courses, but not sure what I did with them. Found my notes. I hoped to have stored the transcriptions to verify what I recall about a specific class. I do not have the transcriptions Continue reading “Bigger is Greater”

Matrix Layer Rotation

I am moving along with a project at work. I have completed the first pass. I am now optimizing the code and testing the system as a whole. As soon as I am done will move to replacing a component with a machine learning (ML) model. I am planning on developing the model using Azure. I would like to see if it is better that using OCR (Optical Character Recognition). Will let you know the results later this month.

I decided to give a try to the HackerRank Matrix Layer Rotation challenge. The challenge is rated HARD and worth 80 points. If interested take a look at the requirements. If interested you can read about how I addressed the problem in this post. Continue reading “Matrix Layer Rotation”

Organizing Containers of Balls

Hope you had a happy Thanksgiving Day with your family. As usual there is lots of anticipation and suddenly it is over.

Some years my wife and I have gone out shopping on Black Friday, but as time goes by, it seems that most of the shopping can be done on-line. For that, the best day seems to be Cyber Monday. Besides the ability of shopping from the computer on Cyber Monday, there was a lot of snow and ice over in the Twin Cities of Minneapolis and St. Paul over the Thanksgiving holiday. One of my wife’s nephews posted on Facebook a video of cars slipping and sliding all over in Minneapolis. Continue reading “Organizing Containers of Balls”