Given a linked list which represents an integer number where every node is a digit if the represented integer. The task is to add a given digit N to the represented integer.
Input: 9 -> 9 -> 3 -> NULL, N = 7
9 -> 9 -> 3 -> NULL
1 -> 0 -> 0 -> 0 -> NULL
Input: 2 -> 9 -> 9 -> NULL, N = 5
2 -> 9 -> 9 -> NULL
3 -> 0 -> 4 -> NULL
Approach: We have already discussed the approach for adding 1 to a number stored in linked list int this article but the code requires reversal of the linked list.
In this post, we have extended the problem to adding any digit to the number stored in a linked list and achieving the same without reversal or recursion.
The idea is to traverse the list and while traversing maintain a pointer to the last node whose value is less than 9. This is because we are adding a single digit to the number stored in the linked list. So, the maximum value of carry (if present) can be 1. Suppose we start propagating the carry from the least significant digit towards most significant digit, then the propagation will stop as soon as it finds a number less than 9.
After the complete traversal of the list in this manner, we have finally reached the last node of the linked list and also maintained a pointer to the latest node whose value is less than 9.
Two cases can arise:
- There can be overflow after adding the number in the last digit i.e. value at the node is greater than 9.
- No overflow i.e. after adding the value at the node is less than 10.
In the first case, we have to propagate the carry from the latest node whose value is less than 9 to the last node.
In the second case, we don’t have to do anything else.
Below is the implementation of the above approach:
1 -> 9 -> 9 -> NULL 2 -> 0 -> 4 -> NULL
Don’t stop now and take your learning to the next level. Learn all the important concepts of Data Structures and Algorithms with the help of the most trusted course: DSA Self Paced. Become industry ready at a student-friendly price.
- Add the given digit to a number stored in a linked list using recursion
- Sum and Product of nodes with value as even digit sum in Circular Linked List
- Sum and Product of all even digit sum Nodes of a Singly Linked List
- Remove all the Even Digit Sum Nodes from a Doubly Linked List
- Remove all the Even Digit Sum Nodes from a Circular Singly Linked List
- Create new linked list from two given linked list with greater element at each node
- Add one to a number represented as linked list | Set 2
- Add 1 to a number represented as linked list
- XOR Linked List – A Memory Efficient Doubly Linked List | Set 2
- Difference between Singly linked list and Doubly linked list
- Convert singly linked list into circular linked list
- XOR Linked List - A Memory Efficient Doubly Linked List | Set 1
- Merge a linked list into another linked list at alternate positions
- Large number arithmetic using doubly linked list
- Number of connected components in a doubly linked list
- Sum of all nodes in a doubly linked list divisible by a given number K
- Product of all nodes in a doubly linked list divisible by a given number K
- Maximum and Minimum element of a linked list which is divisible by a given number k
- Write a function that counts the number of times a given int occurs in a Linked List
- Convert Singly Linked List to XOR Linked List
If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to firstname.lastname@example.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.
Please Improve this article if you find anything incorrect by clicking on the "Improve Article" button below.