Hi CodeForces
'm requested to build a Mathematical Contest Site , The Contest and The Rating System won't be as complicated as CodeForces system since The Answer will be numerical value , so , Any Expert Here To Tell Me The Approach for Such thing and the best system of rating to get nearly accurate level of experience of contestant.
I dont thing cf rating system is not hard, but if you want easy: Something like R = const — (average place during last N contests). For example 2000 — (average place in last 10 contests)
Look up Elo rating system, it's what codeforces uses