Competitive Programming : A Career Sport
Just to put it out there, competitive programming is solving well defined problems under certain constraints using algorithms and standard data structures.
What we mean here by well defined problems is that it is properly defined in terms of what the input is and the number of test cases to run to reach the desired output. We achieve this seemingly organized and tedious feat with the help of computer programs that are generally written on compilers. The language to be used in these computer programs is totally dependent upon the choice of the programmer.
Popularity of Competitive Programming
One of the reasons that competitive programming is popular, is because it serves as a plus point in your resume. Most often a good competitive programmer implies that the person is a good problem solver which is a plus when it comes to interview and placement opportunities. People who are good at competitive programming are often seen getting jobs at Google and Facebook with the help of competitions such as Google Code Jam and Facebook Hacker Cup. Not to mention other product based companies hiring through competitive programming competitions on platforms such as Topcoder, Hackerrank, Hackerearth.
This results in the appearance of competitive programming as a gateway to job in a good company. However, being a good competitive programmer is far from easy. Where learning the basics might take month and years, and then applying those basics in a competition where everyone is as intelligent or better than you, under a time constraint, is very very hard.
Due to this behavior of competitive programming, it appears as exclusive to people who want to get into it, and is often over estimated when started. Bear in mind that a good competitive programmer does not imply a good software developer. But competitive programming does give you an edge in getting that position of the software developer.
Prerequisites for Competitive Programming
While Competitive Programming is a continuous refining process, one does need to start at some point if he is a total novice in the world of programming.
To start off, you need to pick up a language. Preferably C++ and Java are mostly preferred due to the libraries provided by both of them. C++ comes with a library called STL and Java has inbuilt methods and libraries that are essential when it comes to competitive programming. One such example is BigInteger.
For example purposes we will highlight the processes, from the point of view of C++
When you are done with selecting a language of your choice, you need to learn the basics of data structures and algorithms.
- Linked Lists
- Doubly linked lists
- Singly linked lists
- Circular linked lists
- Segment Trees
- Fenwick trees
- Binary Indexed Trees
- Disjoint Data Structures
- Graph Algorithms : BFS, DFS, MST, Dijkstra, Floyd Warshall, Topological sort, Strongly Connected Components
- Greedy Algorithms
- Dynamic Programming
- Searching : Linear Search, Binary search, Ternary search
- Sorting: Quick Sort, Merge Sort, Bubble sort, Insertion sort, Radix sort, Bucket sort, Selection sort, counting sort.
- String algorithms
- Geometry algorithms
The list is just the very basics of what a person needs to have in his arsenal to be a decent competitive programmer. It is in no way the complete list of all the algorithms.
Among all the mentioned data structures, Dynamic Programming is considered to be one of the most difficult programming paradigms to program.
Competitive Programming: All about practice
If you want to be good at competitive programming, then it should be of your top priority. You can't expect to work out 6 hours to build a six-pack abs and code for 1-2 hours and be a better programmer than before. Competitive programming is about practice mostly.
Once you get your arsenal ready, it's time to select a platform to code on. I will list out a few Online Judges where they have archived problem sets and as well as host contess.
- UVA Online Judge
These are few of the Online Judges i can pull out from the back of my head.
Be sure to check the editorials to live contest regularly. Just in case you got it wrong. Checking the editorial also helps influence your coding style a lot. As is the case with most novice programmers that they optimize their code.
The Mantra to succeed
"The beginning is when it is the hardest". That might not be the case with Competitive Programming. It is tough, tedious, time consuming and heart breaking at times. And the only way to succeed is to not give up. If you love what you do, the failures won't effect you. The key to success is not giving up.
Good luck and have a great time programming.