Euler's Totient Function

If you are given a number N, you have to determine how many integers between 1 and N have a GCD of 1 with N.

Binary Search

Finding a number in a sorted array using binary search.

Sieve of Eratosthenes

A beginner's number theory tutorial on Sieve of Eratosthenes.

Faster I/O

Learn how to use faster I/O methods in sport programming.