Recently the competition code royale 2017 ( https://www.codechef.com/COR2017 ) was ended due copied questions and then restarted as it turned out to be a closed contest.
According to the definition of closed contest
“We can restrict access to your contest for a set of usernames or a set of IP addresses. Such contests are closed contests and only available to those people whom you give them access to. These can be used for a targetted audience like your college/school club or a group of friends”.
But the link of Code Royale 2017 can we accessed by anybody and anyone can submit the solution even if he is not registered with the college fest.