How to calculate the complexity of a algorithm.

Question

While I was doing some coding challenges I found that they were asking for an algorithm with an O(n) complexity. I know about the big-O noatation (not all) but what I really need to know is how to calculate them.

I searched a lot in sololearn and stackovwrflow and I finally met with this 1

https://stackoverflow.com/questions/11032015/how-to-find-time-complexity-of-an-algorithm

In that question I found that the asker uses a method for calculating the complexity.
{1+(N+1)+N} = 2N+2

My question is is that way correct and how to calculate the complexity of an algorithm.

Thanks

Answer 1

• Algorithm Design Canvas — https://www.hiredintech.com/algorithm-design

Answer 2

Sεηιrυ ραsαη 👍
You are welcome friend!
I will try to find more resources for explanation, I know what you need, so will try my best!

Answer 3

• Determining the big-O runtimes of these different loops?
https://stackoverflow.com/questions/11094330/determining-the-big-o-runtimes-of-these-different-loops

Answer 4

~ swim ~ that was a good one bro, thanks for that, but I need to re-read again and again

Answer 5

thanks again ~ swim ~ , will definitely learn more from you in the near future

Answer 6

Algorithm complexity (a friendly intro):
http://discrete.gr/complexity/

Answer 7

The most common metric for calculating  time complexity is Big O notation. This removes all constant factors so that the running time can be estimated in relation to N as N approaches infinity. Find some more https://stackoverflow.com

Answer 8

Biraj ~ swim ~ *AsterisK* Danijel Ivanović thanks a lot for those valuable resources. But still one of my problems hasn't solved. Is that method (the thing like {1+(N+1).. }) a valid way?

Nexus how would knowing math only help in this situation?

Answer 9

~ swim ~ I know that thing already. Anyway thanks for sharing them.

But what I really need to know is how those numbers (like n^2, logN) came. I got some knowledge about those numbers from those resources you gave me. But still I'm stucked with them.

Danijel Ivanović and others thanks for spending your time on this 👍

Answer 10

~ swim ~ thanks! it helped a lot 👍

Answer 11

Please check here:
https://www.geeksforgeeks.org/analysis-of-algorithms-set-4-analysis-of-loops/

https://yourbasic.org/algorithms/time-complexity-explained/

Answer 12

Nexus You just have to know how to work with logarithms,exponents,sigmas and some basic algebra. It isn't so hard.

Answer 13

Sεηιrυ ραsαη if you need an in depth explanation,Just check out the wikipedia page on big-O notation. It has explanations on analyzing the running time of algorithms.

Answer 14

Simple answer, YOU'VE TO KNOW MATH, EXTREME XD

Answer 15

Astralis. Thanks man

Answer 16

Thank you so much dear...
:-)

Answer 17

its very simple to calculate the complexity( its total steps taken to complete a process-1)

Answer 18

am i right or not also please tell me about that