Adding Two Numbers Represented by Linked Lists in Java
In this tutorial, we will be learning how to add two numbers represented by linked lists in Java. We will be implementing a class called AddTwoNumbers, which contains a single static method called addTwoNumbers. This method takes in two arguments, both of which are linked lists representing the two numbers we want to add. The method returns a linked list representing the sum of the two numbers.
It's important to note that we are assuming that the two numbers do not contain any leading zeroes, except for the number 0 itself.
Method Implementation
The first thing we do is create a dummy node for our resulting linked list. This is a common practice when working with linked lists as it makes it easier to handle edge cases, such as when the resulting list is empty.
Next, we initialize two variables: a current node, which we set to the dummy node, and a carry value, which we set to 0.
We then use a while loop to iterate through both input linked lists. For each iteration, we calculate the sum of the current digits from each input list, plus the carry from the previous iteration. The carry for the next iteration is calculated as the sum divided by 10.
We then update the current node in the result linked list with the value of the sum mod 10, which gives us the least significant digit of the sum.
After updating the current node, we move to the next node in the input linked lists, if they exist.
Once we have finished iterating through both input linked lists, we check if there is still a carry left. If there is, we add an extra node to the result linked list with the carry value.
And that's it! We have now successfully added two numbers represented by linked lists in an optimized way.
Summary
In this tutorial, we have learned how to add two numbers represented by linked lists in Java. We have implemented a class called AddTwoNumbers, which contains a single static method called addTwoNumbers. This method takes in two arguments, both of which are linked lists representing the two numbers we want to add. The method returns a linked list representing the sum of the two numbers.
We have also learned about the importance of creating a dummy node for our resulting linked list and the use of a while loop to iterate through both input linked lists, as well as the importance of handling the carry value and the edge cases. By following these steps, we were able to add two numbers represented by linked lists in an optimized way.
Solution Code:
