Google released the PDF code of Chrome just a few days. I took a look at it. This file (core/src/fpdfdoc/doc_vt.cpp) is an example of how the code looks.

Sometime later it dawned on me that this code is built out of only low level pieces. There are almost no algorithms extracted to functions.

An example would binary search. There are five copies of binary search hidden in just that file. No wonder this file is 1864 lines of code.

What else would be hidden in there?