SCC0106 - Editorial
PROBLEM NAME: Who is my friend.
Author: Learners Club
Prime Numbers, Euler Totient function
In short, We are required to find the count of all the positive numbers less than N which are coprime to the given number N.
This is a direct application of Euler Totient Function.
Look up wikipedia to understand it and give it a try on the practice section.
Important point to know is that For N = 1 the Answer is 1, Find out why… ?