Sherlock and the Valid String

It is Sunday March 15, 2020 and it is a sunny day in the Twin Cities of Minneapolis and St. Paul. The current temperature is about 22 F. It has gone up a few degrees since I woke up today. The high is expected to be in the low 40’s. It seems like it is going to be a nice warm winter day.

It has been a crazy week. The count of confirmed COVID-19 cases in MN according to the StarTribune up to last Friday was 9. That said; my wife and I decided to get some supplies (e.g., two packages of toilet paper at Costco) and remain at home (with a few exceptions) until the pandemic is under control. I will write a set of posts regarding COVID-19 in a separate category. Continue reading “Sherlock and the Valid String”

Java Streams

A few minutes ago my wife called me up to the kitchen to help her. She needed Grand Maniere for an Italian nonna’s apple cake she was making. In addition to the apples, she likes to add raisins soaked in liquor. She decided to use Grand Maniere because she found a large bottle in the liquor cabinet. She could not remove the cork so she called me for help. As I was attempting to open the bottle I asked if she remembered when we got it. It seems that we bought the bottle when we lived in Maryland; that was many years ago.

The cork disintegrated when I was opening the bottle. The bottle was standing up and with the years the cork dried up. We keep our wines in an angle in our cellar, but the hard liquor in our cabinet is standing right side up. We seldom consume hard liquor. The Grand Maniere smelled fine and my wife was able to soak the raisins. Each time she fixes this dessert she tries to make it a little different. In my opinion, apples, raisins and walnuts go very well together. Will let you know in my next post how this cake turned out. Continue reading “Java Streams”

Experimenting with RTree – JARs Created and Installed

It is Saturday morning and I am starting the text for this post. The process I used to get the RTree code ready and integrated into a test program that I will use to experiment in the next few days will be covered. As usual issues seem to appear and they need to get resolved.

Yesterday my wife and I brought in from our garage freezer a full pork butt that we purchased a month or so ago at Costco. Not sure how heavy it is but I recall looking for the largest package when we purchased it. Typically we split the butt into the two pieces that are packaged together. This time we decided to cook both at once. That way we can freeze most of it and use it as needed during the next month or two. Continue reading “Experimenting with RTree – JARs Created and Installed”

Larry’s Array

Over the weekend my wife and I tried baking baba (Italian yeast cake) using a large mold. Typically baba is baked in individual small molds but it takes a while to grease and fill them. We tried for the first time using a large mold. All was going well until we put the mixer bowl covered with plastic in the oven with the lights on for it to ferment and double in size. After a couple hours the dough had pushed its way out of the bowl and spilled over the oven floor. We had to clean the mess before baking. We also moved the contents of the bowl into the large baking mold. Continue reading “Larry’s Array”

A* Search Algorithm

As I mentioned in my last post, I read the article “A* search: what’s in a name?” by James W. Davis and Jeff Hachtel. If interested, you may find the article in Communications of the ACM, December 2019, Vol. 63 No. 1, Pages 36-37. The article deals with the name of a search algorithm that was originally published in 1968 by Peter Hart, Nils Nilsson and Bertram Raphael of Stanford Research Institute.

My interest was not much about the name but to be able to experiment and understand the algorithm. There are so many algorithms in Computer Science that adding one more to my list is always welcomed. I do not plan on memorizing the algorithm but if the time comes when I might need to search a graph, I will have one more choice in my toolkit. Continue reading “A* Search Algorithm”

Emma’s Supercomputer or Two Pluses

I started the Emma’s Supercomputer HackerRank problem last week. This problem is also known as Two Pluses. Last week I got quite busy so I did not have time until this morning to complete the solution for the problem. Last Wednesday I was able to get my code to pass 20 of 23 test cases. I figured out what I could do to pass the last three, but until this morning I had no time.

The problem is ranked Medium difficulty, but I spent time like it was more difficult than that. Read the description in the HackerRank web site. The description is straight forward. I understood what the idea was with the plus signs, but from there to implement a solution that is a different story.

Continue reading “Emma’s Supercomputer or Two Pluses”

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”

Almost Sorted

In the past few days there have been several announcements by both car and device manufacturers that self driving cars are almost a reality and to make that possible new and cheaper devices are being introduced to help.

It seems that newer LIDAR devices are improving in range and precision while their prices are coming down. This should help. On the other hand researchers are working on algorithms to check that sensors are getting more reliable. I read an article today that LIDAR systems can be tricked to not detect something or to detect something that is not there. Continue reading “Almost Sorted”

3D Surface Area

Good morning. It is Monday January 06, 2020. Last year’s holiday season was rather long. Christmas fell on Wednesday so most companies gave Tuesday as a holiday. On the following week, most companies do not give New Years Eve day as a holiday but most people take it as a personal holiday or vacation day. I work every day (included weekends and holidays). Granted that on weekends and holidays I only sit in front of my computer for only two 2-hour blocks. Continue reading “3D Surface Area”

The Grid Search

It is Saturday morning and I am in my second block of the day. I typically do a couple 2-hour blocks on weekend days. As usual I got up at 05:00 AM and got breakfast ready. During breakfast my wife mentioned that she was not feeling well. Apparently she caught a cold or flu.

We had invited for lunch a couple of her brothers and spouses. One of her brother’s birthday was yesterday.  We decided to change the menu and postpone lunch with family for next Saturday. We had planned a couple of Italian dishes and I was already savoring them. We both enjoy cooking but decided on a single simpler course for lunch. Continue reading “The Grid Search”