Every beginner computer science student would have once wondered why do we find shortest path in graph or what is the use of trees, are we going to play josephus circle using circular linked list?

So, this article talks about the importance of Data structures and algorithms in real world in the reference of COVID-19.

The present outbreak of a corona-virus acute respiratory disease called COVID-19 has resulted in a major epidemic. The main reason why coronavirus is a major problem is because it’s spread can be modelled by a tree.

Before the world took lockdown measures, estimates stated that each infected person was infecting between two to four other people. This number is called R_{0} (R-naught), a mathematical denotation that indicates how contagious an infectious disease is. For instance, if a disease has an R_{0} of 15, a person who has the disease will transmit it to an average of 15 other people.

Three possibilities exist for the transmission or decline of a disease, depending on its R_{0} value:

- If R0 is less than 1, each existing infection causes less than one new infection. In this case, the disease will eventually die out.
- If R0 equals 1, each existing infection causes one new infection. The disease will stay alive and stable, but there won’t be an outbreak.
- If R0 is more than 1, each existing infection causes more than one new infection. The disease will be transmitted, and there may be an outbreak or epidemic.

Importantly, a disease’s R_{0} value only applies when everyone in a population is completely vulnerable to the disease, as in the case of COVID-19 where no one has been vaccinated, no one has had the disease before and there’s no way to control the spread of the disease.

In our model — R_{0} is the average number of children each node in the tree has. This means — each node in our tree has (on average) between two and four children.

If you’ve studied trees to any depth, you know this is going to get very large, very quickly.

The early objective of health organizations worldwide was to reduce R_{0} to around one (or less). If R_{0}= 1, then each leaf node in our tree now becomes the head of a linked list. Each person is infecting exactly one other person, in the same way, that a (singly) linked list has a reference to the next node in the list.

If R_{0}< 1, then at some point a person will infect no-one else, and the line of infection (for that leaf) is broken. We can model that in code by having the node point to a null reference, meaning it is the ultimate node in the linked list.

One way to “solve” the corona-virus situation is to change the behaviour of the virus so it can be modelled by a collection of (eventually finite) linked lists, rather than a tree. Trees, Graphs & Linked Lists aren’t only used in **FAANG** interviews, but are actually very useful in modelling and solving real-world phenomenon.

Therefore, Stay Safe and Stay inside to break the chain of Corona-virus.

Attention reader! Don’t stop learning now. Get hold of all the important DSA concepts with the **DSA Self Paced Course** at a student-friendly price and become industry ready.

## Recommended Posts:

- Introduction to Data Structures | 10 most commonly used Data Structures
- Bring Out The Geek In You During COVID-19 Outbreak
- How Hackers Are Using Coronavirus To Scam People?
- What is the Role of Artificial Intelligence in Fighting Coronavirus?
- How to Deal With Layoffs During Coronavirus Pandemic?
- How can one become good at Data structures and Algorithms easily?
- What is the difference between Front-End and Back-End Web Development?
- Overview of Data Structures | Set 3 (Graph, Trie, Segment Tree and Suffix Tree)
- Persistent data structures
- Disjoint Set Data Structures
- Linked List representation of Disjoint Set Data Structures
- Design data structures for a very large social network like Facebook or Linkedln
- Data Structures | Misc | Question 5
- Difference between Stack and Queue Data Structures
- Data Structures and Algorithms Online Courses : Free and Paid
- Why companies like Amazon, Microsoft, Google focuses on Data Structures and Algorithms : Answered
- Live Classes for Data Structures and Algorithms: Interview Preparation Focused Course
- Difference between Linear and Non-linear Data Structures
- Why Data Structures and Algorithms Are Important to Learn?
- Static and Dynamic data structures in Java with Examples

If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.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.