Maximum Subarray Sum – Kadane’s Algorithm

A day or two ago I was browsing and saw a question regarding finding the maximum sum of a sub array given an array of integers. I decided to do some exploration on the Kadane’s algorithm. I tried a couple brute force implementations. I then went for an implementation using the algorithm.

Maximum Subarray Sum

Given an integer arry nums, find the contiguous subarray (containing 
at least one number) which has the largest sum and return its sum.

The problem definition is quite simple. Implementing a brute force is not too bad but it is quite slow. After a couple implementations we will use Kadane’s algorithm in the third approach. Continue reading “Maximum Subarray Sum – Kadane’s Algorithm”

Nona’s Kitchen – JavaScript

Good morning! It is Sunday of the Thanksgiving Day 2020 weekend. Time seems to be passing by quite quickly. Earlier this morning I was reading an article regarding the Pfizer COVID-19 vaccine. It seems that there are still some items that need to be addressed before that vaccine becomes readily available in the USA. Accordingly to the article, we should achieve herd immunity summer 2021. Let’s keep our fingers crossed. In addition there are many other laboratories that are about the same stage as Pfizer. It is safe and reasonable not to depend on a single source.

While I was about to finish editing this document and getting ready to post it, my wife called me to go grocery shopping to Trader Joe’s. On weekends, unless I get up earlier (around 04:00 AM), I typically have time to work on a single 2-hour block. I can extend the block if needed, but if I am doing something with my wife, that tends to put an end to work on that day. Continue reading “Nona’s Kitchen – JavaScript”

Validate Binary Search Tree – Revisited

Hope you enjoyed Thanksgiving Day 2020. My wife and I did even though it was just the two of use for late lunch. We prepared our usual menu with some minor twists. The menu was a young turkey (we usually cook a 20+ lbs bird) which came in at around 11 lbs. with potatoes casserole and meat stuffing (we not prepare the popular / traditional bread based kind). For desert we had monkey bread which we got from one of our neighbors. We had a little more than we should, so we decided to skip our after lunch espresso.

For the turkey, we added some spices, a little garlic clove, some butter and apple vinegar. We inserted a thermometer and cook it to 175F. We then took it out of the oven and let it rest. Typically the temperature rises north of 180F. Since the turkey weighted 11 lbs., the temperature only went up to 178F. Continue reading “Validate Binary Search Tree – Revisited”

Continuous Subarray Sum

Tomorrow is Thanksgiving Day 2020. My wife finished preparing three containers with cheesy potatoes casserole. She has been making this dish as far as I can remember. Due to the ingredients we tend to have it once or twice a day. I will provide the recipe and some pictures on tomorrows post. If I am not able to solve a problem and generate a post, will generate a post as soon as possible.

We are still in the midst of the COVID-19 pandemic. About two million people around the world have die of complications related to the novel coronavirus. My wife and I have some friends’ originally from Vietnam. We learned today that one of them is in the hospital and the other barely making it at home. One of my wife’s brothers has been diagnosed with COVID-19. He, his wife and two kids are in quarantine at home. Our best wishes and our thoughts go out to them for a quick and safe recovery. Continue reading “Continuous Subarray Sum”

Validate Binary Search Tree

It is a gloomy day in the Twin Cities of Minneapolis and St. Paul. The good thing is that we have about two days until Thanksgiving Day 2020. This year we are cooking an 11 lbs. turkey. Typically my wife and I make an 18+ lbs. bird. Not only that but we are dropping half of it at our granddaughters place. On Thanksgiving Day we will be connecting with family via Jitsi and Skype. Continue reading “Validate Binary Search Tree”

Construct Binary Search Tree from Pre Order Traversal

It is Thanksgiving Week 2020 and we do not have a winner in the 2020 Presidential Elections yet. The amount of fraud in this year’s elections has been unprecedented. My comment has nothing to do with politics. It is just based on common sense for individuals 12 years of age and older. I have friends and relatives living in different parts of the world. Their confidence and respect in the USA is almost (never generalize) gone.

On multiple occasions and referring to different topics, I have mentioned in this blog a technique used when people want to understand the positions of each other. First both argue on behalf of their own positions. Then, and this is the key of the technique, they switch positions and argue in favor of the opposite position. It is amazing what you can learn about different ideas when you use this technique. The reason for this tends to be based on facts and logic. Continue reading “Construct Binary Search Tree from Pre Order Traversal”

Print Immutable Linked List in Reverse

Hi gals and guys. Hope you are doing well during the COVID-19 pandemic. It seems that most of us are somewhat tired following the basic rules that reduce the spread of the coronavirus. By relaxing the rules in the past few months, the numbers of COVID-19 infections, in most cities worldwide, are going up. Note that the issue is the number of infections, not the number of deaths. Infected people may need hospital services. If the number of patients is larger than the capacity like it was when this thing started, then we have a problem. At this point in time, people with most infections per 1,000, is people in college age. Please follow the rules! We all benefit from it. Continue reading “Print Immutable Linked List in Reverse”

Maximum Length of a Concatenated String with Unique Characters

Hello and hope you are doing well. Today the temperature went up to 51F in the Twin Cities of Minneapolis and St. Paul. I did not get a chance to go out. Hopefully we will experience a mild winter this year.

Sorry but it is the middle of the week (hump day) and I do not have much to tell you. Time appears to be passing quite fast. Many cities in the country are upping COVID-19 restrictions. It is going to be an interesting Thanksgiving Day coming up in about a week. My wife and I will be preparing a meal. Will take some to our family and on our way back will get on-line (Jitsi or Skype) and will enjoy the meal. Continue reading “Maximum Length of a Concatenated String with Unique Characters”

First Web Application – Node.js

Hope you are having a nice day. Today is Tuesday. Unless I am mistaken, it has been three weeks since Election Day and as far as I know the results for the presidential election are still up in the air. Hopefully we will find out the results in the next few days.

Next week is Thanksgiving Day. My wife and I were planning on having very few people over, but after further deliberations, we decided that we will skip and celebrate Thanksgiving 2021 with family and friends. Based on what is going on with COVID-19, it seems that a few vaccines will be made available early next year. By November 2021 we expect that most things would be back to normal; that is, the new normal. Continue reading “First Web Application – Node.js”

Simple and Second Web Servers in Node.js

I am about to call it a day. It is dark and cold (25 F) in the Twin Cities of Minneapolis and St. Paul. I am in my office attempting to finish this post while my wife is upstairs in the living room wrapped in a blanket. Tomorrow morning we will wake up to a balmy 12 F. What else can I say?

I am reading and experimenting with the content of the book “Get Programming with Node.js” by Jonathan Wexler. I am currently on page 55. Expect to be done with towards the end of next month. At that time I will switch to experiment with Deno. Then I will move on to generate and post a first pass of a storage server. It should be a lot of fun. Continue reading “Simple and Second Web Servers in Node.js”