LeetCode 445 Add Two Numbers II in Java

In this post we will solve the LeetCode 445 Add Two Numbers II problem using the Java programming language. We will generate two implementations of the function in question. The first will use two stacks while the second will reverse the singly linked list. When reversing linked lists we will implement an iterative and a recursive set of functions.

You are given two non-empty linked lists representing two non-negative integers. 
The most significant digit comes first and each of their nodes contains a single digit. 
Add the two numbers and return the sum as a linked list.

You may assume the two numbers do not contain any leading zero, except the number 0 itself.


o The number of nodes in each linked list is in the range [1, 100].
o 0 <= Node.val <= 9
o It is guaranteed that the list represents a number that does not have leading zeros.

Follow up:

o Could you solve it without reversing the input lists?

Related Topics:

o Linked List
o Math
o Stack

We are given two singly linked lists with digits representing two non-negative numbers. We need to return their sum in a singly linked list. If interested in this problem I suggest you visit LeetCode and get the current version of the problem. Sometimes the requirements are updated. Continue reading “LeetCode 445 Add Two Numbers II in Java”

High Point in Array

Good morning! It is Friday and the weekend is just around the corner. In the Twin Cities of Minneapolis and St. Paul we received our first snow dusting of the season. Yesterday early morning I drove my wife to a healthcare facility to get a radiological exam. Traffic was heavier than what we expected. We got back home around 09:00 AM. The rest of the day ended for me at 19:00 PM. It was a very long and exciting day.

As the weather changes, I have slightly modified my workdays. I work in 2-hour blocks. The blocks are dictated by the EyeDefender app. I tend to work four to five blocks during the week and one to two on weekends. After each block I get on a stationary bike and pedal backwards for about two minutes and forward for six. This gives me over half an hour of exercise per day and half on weekends.

Starting this week, I will not stop immediately after EyeDefender tells me to do so. Will continue with the bike exercise after each block. Doing this will reduce the blocks to four on workdays. I guess it is better to continue working past the two hours until I reach a normal breaking point based on the task at hand. Will let you know my findings as far as productivity is related early next year.

One last thing, most of the times that I generate a post, I check on the number of subscribers. Today’s count is 10,025 subscribers Thanks a lot!!! This implies that in the very near future I will, in addition to this post, start a YouTube channel with similar content or will just switch to YouTube and discontinue this blog. One way or the other, I will be getting the necessary video hardware and software tools, and will start experimenting with them. I am planning on having the YouTube channel up and running by January 2022. Continue reading “High Point in Array”