Coin Change

Hope you are doing well and keeping safe! Last evening my wife and I, after stopping a movie we were watching on Netflix, went to bed. It was still snowing on and off. We were both very tired. Today when we were having breakfast, we noticed that the driveway and path to our door had been cleared of snow. We did not hear a thing. That confirms we were really tired last evening.

One of my best friends (have two sent me the link to the article “Top Universities Took Billions in Unreported Foreign Funds, U.S. Finds”, by the Wall Street Journal. The article is quite interesting. It shows how China is gifting money (there are no free lunches) to top USA learning institutions (mostly Ivy League universities) in order to take / steal intellectual property, allowing China to avoid developing technologies at much higher costs. This was discovered due to the fact that those same institutions have been forgetting to pay the associated gift / donation taxes. Shame on you Cornell University! Continue reading “Coin Change”

Dynamic Programming Revisited

Today in the Twin Cities of Minneapolis and St. Paul we had snow on and off for several hours. It does not seem we have any accumulation on the road surface. This might change tomorrow. Snow is expected for most of the day. It seems winter has arrived.

A friend mentioned the article “Tokyo citizens may have developed COVID-19 herd immunity, say researchers” by Sally Robertson. If interested, read the article and then continue reading this post… Continue reading “Dynamic Programming Revisited”

Backspace String Compare

It is a Saturday morning in the Twin Cities of Minneapolis and St. Paul. As we have been doing for a few months, my wife and I drove to the Costco store in Minneapolis, met with our son and went grocery shopping. Today we were not able to find Three Berry Blend bags. We got separate bags of strawberries and blueberries. Our son will stop later today at the Costco in Eagan. MN and will see if he is able to find a couple bags of mixed berries and a box of pens that we forgot while in Minneapolis.

This week I watched the Association for Computing Machinery (ACM) webinar “Lessons from COVID-19: Efficiency vs. Resilience” by Moshe Y. Vardi. It seems that the webinar is only accessible if you are an ACM member, which I am. I enjoyed the point he made of efficiency versus resilience not only at the software but also at the political level. At no point he mentioned politicians or political parties. In my opinion, it is a very good one-hour webinar worth your time. Continue reading “Backspace String Compare”

Print a Binary Tree in Vertical Order

Yesterday morning while looking at the news on my phone, I ran into Print a Binary Tree in Vertical Order | Set 2 (Map based Method) by GeeksforGeeks. Without reading the article I just twitted it. I tend to do this with software related articles that call my attention. That way I can go through my Twitter history and read such articles when I have enough time to do so.

By 07:00 AM I was down in my home office ready to experiment and have fun. Most weekend days I work one 2-hour block, buy yesterday my wife and a couple friends were getting together to catch up on things. They sit outdoors on the deck of the house of the gal hosting the gathering in order to keep social distancing due to the COVID-19 pandemic. Since we live in the Twin Cities of Minneapolis and St. Paul, such gatherings should be coming to an end shortly. The high temperature for the following two weeks is forecasted to be in the mid to upper 40’s. That said; today I have enough time for two blocks!!! Continue reading “Print a Binary Tree in Vertical Order”

First Unique Character in a String

It seems that time is passing faster and faster. The reason seems to be the lack of variety in our lives. The COVID-19 pandemic for most has imposed limiting factors for social activities. I do not mind getting on-line with coworkers, friends and family, but nothing beats in-person interactions. Hopefully things will get better in the next few months. It seems that several pharmaceutical companies are moving along with their tests for their vaccines.

I selected LeetCode problem 387 First Unique Character in a String. It is catalogued as an Easy problem. That said, like most things in life, there are different ways to skin a cat, but one is best given your specific circumstances. I get a kick when I read about competitive programming. I have a hard time understanding the concept. To me it is like giving a brush to Michelangelo and ask him to paint as fast as possible the ceiling of the Sistine Chapel in the Vatican City. Continue reading “First Unique Character in a String”

Partition Labels in Java

I was planning on working a couple blocks (a block entails 2 hours) on this post but ran out of time. The reason for it is that I will be collaborating with a group by posting some of their articles in my blog. It appears that the group uses Google Docs to create the text for their posts. For text I use Microsoft Word and for diagrams Microsoft Visio.

I have never before directly included a Google Docs on WordPress. That is the reason I had to learn the process, and check for possible caveats. That took some additional effort and time. If interested it seem that the section Use Google Docs to Post to WordPress on Resource Center provides the necessary steps.

Posting to WordPress from Google Docs is easy with the add-on for WordPress.com (Jetpack). 
Before continuing, make sure you have a free Google/Gmail account, 
that Jetpack is installed and configured on your WordPress site, 
and that you have registered with a WordPress.com account through Jetpack.

Make sure you take into accounts the prerequisites paragraph in the section in question. I just made sure I complied. At this time I am using the FREE version of Jetpack for WordPress. I am considering a paid subscription but have not committed to it yet. Continue reading “Partition Labels in Java”

Number of Islands – Java

Last evening before going to bed, I left a window in the kitchen opened just a crack. The temperature was forecasted to drop down to 37F, so I hopped it was going to be fine.

A few minutes past midnight I woke up. It felt somewhat chilly. I closed the window and checked the temperature in the upper level zone. It was at 68F which is at what we keep it during the winter months. I turned on the heat in the zone and went back to bed. During the rest of the night I heard the furnace kick in a couple times.

During breakfast my wife asked if windows were closed and the furnace was on. I told her about my midnight adventure. We agreed on leaving windows closed from now on until next spring. The system at home has an air exchange unit so it makes sense to keep the windows closed and the temperature at 68F. Continue reading “Number of Islands – Java”

Masking Personal Information

Earlier this morning while having breakfast with my wife, around 06:30 AM she noted that the day was quite dark. I replied that this is normal this time of the year, especially because Daylight Savings in the United States was extended since the last update.

Around 07:00 AM, after showering and getting dressed, I descend to my home office. Around 10:00 AM I prepared coffee for my first break of the working day. It was sunny and windy with a temperature in the high 40’s. Hopefully the weather will remain like that for the rest of the day.

While browsing the LeetCode web site problem 831 Masking Personal Information called my attention. I develop software and systems that deal with medical records and images which need to be de-identified. This problem seemed to contain a very reduced set of data that needs to be anonymized. Continue reading “Masking Personal Information”

Count Negative Numbers in a Sorted Matrix

UPDATE UPDATE UPDATE

I wish to correct a statement in this post. I mentioned that my wife and I received ballots for the next presidential election. It turns out that the envelopes contain requests for ballots, not the actual ballots. One way or the other we will vote as usual in person at a assigned polling center on Election Day.

I have been reading a few articles regarding the next presidential elections. Some Democrats do not appear to want to use a voter ID to reduce election fraud. The reasons, which you may find on-line, seem to be somewhat childish to say reject a national voter ID registration and card. They are used in most countries.

Due to the COVID-19 pandemic (thanks China), the brilliant idea (I am being facetious) is to have voters mail in their completed ballots using the secure  USPS. In addition you can request a ballot be mailed to you in most (not sure if in all) states. But that is not all, my wife and I live in Minnesota and we have received two (2) unsolicited ballots which we will not use. We will keep them as a souvenir to remember, what I consider, the last nail in the coffin for democracy in the USA.

I am not stating that all people or political parties will commit election fraud. But if you read the news, and we are still about a month away from elections day, fraud is happening all over. Fresh ballots are found in bulk, completed ballots which favor of the Republican candidate have been ditched. What prevents me or any other 3,460,663 registered voters in the state of Minnesota to vote once by mail and a second time in person at a voting site on Election Day? And that is only considering Minnesota.

Election fraud has been around in the US for at least five decades. We have never before seen so much fraud prior to Election Day. So what is going to happen Election Day? After the count of fraud ballots is completed, chances are that there are going to be more votes than registered voters. The elections might be dismissed and we will have to wait a few months or year before a mechanism is deployed (i.e., voter ID) to reduce (eliminate would be too much to hope for) fraud.

All of the turmoil to occur (i.e., riots, protests, looting, lack of groceries) will put the USA at a disadvantage to counter the push of China to dominate and enslave the world (including the USA). Who knows, we might have to buy all Chinese products from Chinese companies (bye bye Apple). We will be forced to work 996 (09:00 AM – 09:00 PM 6 days a week).

Please think before you vote. I personally want to maintain our way of life with some few changes to capitalism and democracy. Continue reading “Count Negative Numbers in a Sorted Matrix”

Merge Two Binary Trees – Java

It is Monday morning. I got up earlier to finish the code and this post. Hope to be done before 06:00 AM. Today is my wife’s birthday. She is an evening person. Every morning I get up, fix breakfast, and then wake her up.

This year due to the COVID-19 pandemic (thanks China) we have not planned a celebration. Dates tend to shift by a day on non-leap years. Yesterday I received a message with Google photos that we took on yesterday’s date several years ago. Last year for her birthday we were with some family, friends in Rome, Italy. In the evening we all had a nice dinner and walked to the Fontana di Trevi and tossed three coins. That was a nice way to close the day. We like Italy and have been there many times. Perhaps next year things will be back to the new normal and will be able to celebrate once again in Rome. Continue reading “Merge Two Binary Trees – Java”