The contest went unrated for me too. Quite new to the platform and not sure if that is justified or should be considered as a system bug. Could anyone clarify please? The rating went down from 1000+ to 776 after removal of the rating contribution of this contest.

If the optimal team has students with maximum smartness M and minimum smartness m, would having students with smartness X such that m≤X≤M the answer will not change.

Is it me or the hint should rather read like this:

If the optimal team has students with maximum smartness M and minimum smartness m, would having students with smartness X such that m≤X≤M change the answer?