Summary A collection of Andrew Koenig’s “Much Ado About Nothing” topics on Drdobbs. Pointer Arithmetic: A Major (Dis)advantage of C and C++ The gist: referencing an array by indexes and by pointers are equivalent in C, but when using pointer reference, it hard to check array bounds. That’s why …

GCD Definition GCD of two integer is the largest integer that divide both given integers. Calculation Factorization method Find the integer factorization of the two integer first, find the common factors and multiply together. Euclidean Algorithm The key idea of Euclidean algorithm is to use the smaller integer to …

What file permissions the web documents should have in order to make development process easier? The answer depends. For my use case, I want to avoid using sudo to copy documents from the user’s home to the Apache document root directory every time I want to update a file. Because the /etc/www directory owned by …

I was stuck for a while when solving the leetcode problem Remove 9 . After sketched a relatively complicated solution, I decided to give myself a hint by reading the discussion board. It is all about numeric base conversion! When I tried to write the routine to convert a decimal number to a number in base 9, I found it …

When reading the book “Accelerated C++” years ago, I was impressed by the effectiveness of loop invariant in ensuring bug-free of many functions implemented in the book. That reading opens me another door to formulate and solve some of the error-prone programming problems. The idea of loop invariant is a …