# NOJ Rating System

Inspired by CodeForces, the basic idea of NOJ Rating System is to generalize Elo rating to support games with multiple participants.

In general, each community member is characterized by value $r_{i}$, — integer number. Roughly speaking, the higher value means better results in the contests. Rating is calculated/recalculated so that the equality strives to be correct:

$P_{i,j}=\frac{1}{1+10\frac{r_{j}-r_{i}}{400}}$