Wcipeg 2017-2018 Test
The Carol Economy is a set of people who interact and share hearts (<3) with each other. In order to be part of the Carol Economy, each person must be friends with every other person. Carol is trying to set up a larger Carol economy between some of her friends. There are N people, and K pairs of people know each other. Help Carol calculate the amount of new friendships that must be made.
The first line of input contains the integers N (1 ≤ N ≤ 1000) and K (0 ≤ K ≤ 106).
Output the number of new friendships that must be made. This number is guaranteed to be non-negative.
C++03, PAS, C, HASK, ASM, RUBY, PYTH2, JAVA, PHP, SCM, CAML, PERL, C#, C++11, PYTH3