Big O notation is commonly used to describe algorithm performance. But modern hardware makes performance analysis much harder than it used to be. In this short article we give three interesting examples to illustrate the limits of big O notation.

Big O notation is commonly used to describe algorithm performance. But modern hardware makes performance analysis much harder than it used to be. In this short article we give three interesting examples to illustrate the limits of big O notation.
We investigate a simple way to speed up std::sort from the standard library
A few days ago I wrote a small app to illustrate one of the articles I was preparing. Basically the program was loading a file from the hard disk, sorting it, and then outputting to another file only unique values (by omitting duplicates). The function for writing unique values to a file looks like this:…