Hi everyone! I created a small group here which is open for public. There will be 3 5-hour contests held there featuring 3 problems each and the problems are taken from olympiads of different countries as well as problems from other sites (though these are rare) The contests will be in ACM-ICPC mode. (since this is the default CF mode)
Since almost all of the problems are unoriginal, it is very likely that you might have seen some of the problems before. Everyone is welcome to join the group and participate in any contest anytime.