Public documentation for contestants

This repository contains sample code for IOI contestants, that shows how to perform basic operations in C++, Java and C#.

Notes on basic input/output:

• In C++, use sync_with_stdio(false) for fast cin/cout.
• In Java, BufferedReader seems to be faster than Scanner.
• In Java and C#, printing seems to have expensive overhead. In Java we can use BufferedWriter (remember to flush() before exiting!), and in C# we can use StringBuilder.
• Java and C# seem to read very long lines slower than C++. Best to avoid long lines if possible.
• Java's ArrayList is sometimes slower than normal arrays.