Ranking Mechanisms | CodeChef
Ranking Mechanisms

This page lists all the types of rankings that we use for our contests. Presently we have three types of ranking mechanisms that we use in our monthly contests. They vary depending on various combinations of score, time and penalty for wrong submissions.

1. ACM Style Ranklist (ACM)

  • You will be ranked on the basis of the score you get.
  • In case of a tie, the rankings will be determined by 'Total Penalty', which is the sum of the total time elapsed when you submitted the correct submission plus a penalty of 'X' minutes for every rejected submission (Wrong answer, Time limit exceeded, Runtime Error) for a problem you solved. The lower you Total Penalty, the better.
  • The total time is the time taken to solve a problem since the start of the contest.
  • Getting Compilation Error does not contribute towards the 'X' minutes penalty.
  • The time elapsed or penalty is not considered for any unsolved problem.
  • This type of ranklist is typically used in CodeChef Cook Off’s (where X = 10 mins), external contests (value of X will be mentioned on the contest page) and ICPC regional contests (where X = 20 mins). E.g: CodeChef's October Cook-Off 2014.

2. IOI Style Ranklist (IOI)

  • You will be ranked on the basis of the score that you get.
  • There are no penalties for wrong submissions, so you can submit solutions as many times as you'd like.
  • However, only your best correct submission will be considered.
  • Ties are broken according to the times each participant reached that score (This is not what happens at the IOI, but we take the liberty to break ties here).
  • This type of ranklist is used in CodeChef LunchTimes. E.g: CodeChef's Lunchtime contest.

3. Score Based Ranklist (LONG)

  • You will be ranked only on the basis of the score that you get. The score is the total number of points that you get in a contest.
  • There are no penalties, so you can submit solutions as many times as you want.
  • The time elapsed is not considered.
  • The ties are unresolved.
  • This type of ranklist is typically used in CodeChef Long Challenges. E.g: CodeChef's October Long Challenge 2014.

These are the three types of ranking mechanisms that we have today. If you have a new mechanism in mind that you would like to see on CodeChef, please feel free to write to us at feedback@codechef.com