Stacks to Reverse Order

UPDATE – Added a couple classes and implemented reverse method to reverse the linked list in segments. I will leave this post and move on to a different subject on the next one.

It is a cold Sunday in the Twin Cities of Minneapolis and St. Paul. The forecast called for a winter storm starting last Friday around noon ending Saturday afternoon. The forecast called for 6 to 9 inches of fresh snow and wind blowing up to 45 mph. Due to the forecast, people visiting the area last week or people with plans for the weekend decided to move their schedules and leave the Twin Cities earlier. Airports were crowded and flights were overbooked. When all was said and done, the Twin Cities received about 6 inches of fresh snow. Some places further out received considerable higher amounts (e.g., Hovland, MN 16.5 inches).

Continue reading “Stacks to Reverse Order”

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”

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”

Finding Intersection

Earlier this morning I spoke with my friend Gustavo. We know each other for most of our lives. We started kindergarten together. Today we are both married to our respective spouses and have kids and grand kids. We get on Skype about once a month always on a Friday at 06:00 AM and have a great time catching up.

He studied geology and currently owns a company that was started by his dad. He bought out his siblings and with time has grown his company quite a lot. Last time we got together was for a geology convention last year in the Twin Cities of Minneapolis and St. Paul. We had a great time with our spouses dining, dining and doing tourist things. The only thing of the trip they did not like was the snow. The show was in February and there was a lot of snow and of course cold temperatures. Continue reading “Finding Intersection”

Sliding Window

I been reading, watching videos and experimenting with the Universal Windows Platform (UWP) and cpp/WinRT most of the day. On this final block I decided to take a break and make a post in my blog. I want to get some software done before the end of the day this Wednesday. Will let you know if I meet the deadline.

I noticed in my Gmail that JAVAAID had posted a video on YouTube titled “Sliding Windows Technique”. It called my attention because the Rabin-Karp algorithm is based on a sliding window technique.  In the past few months I wrote a post on the subject and named it “Rabin-Karp Algorithm” (not too creative on my part). Continue reading “Sliding Window”

Missing Two

Usually my youngest son calls on his way to work. Is almost 10:00 AM and have not heard from him. I work from home so I am able to receive his calls pretty much any time. I do not like to call him because he works out in the mornings and has to go home, get ready and drive to work. His time varies from day to day. We have this unspoken arrangement that if he does not have a chance to call we will do so the next day.

The arrangement is exactly the opposite on weekends. I tend to call him as soon as my wife and I head out for the first activity of the day. Typically is on our way to or from shopping for groceries or running any other morning errand. Continue reading “Missing Two”

Re-Space

UPDATE – The format for the code for the class TrieNode has been addressed. Sorry for the inconvenience.

It is Friday and my youngest and family will be arriving this afternoon for a weekend long visit. My wife and I are getting ready for their arrival later today. We all enjoy good food so we have an extensive menu planned which includes fugazza, pasta carbonara with lots of pancetta, beef roast with a homemade tomato sauce, limoncello cake and different alcoholic and non-alcoholic beverages.

Let’s get to the main subject of this post. I tackled problem 17.13 from the Cracking the Coding Interview book. The problem is name Re-Space. Continue reading “Re-Space”