When I submitted my solution to the problem, I got an unexpected result named "Denial of judgement". The checker log printed "Model solution returns with verdict TL and exit code -1". I submitted another solution that just got AC these days, but it got the same result "Denial of judgement". Someone told me this is a case of std getting TLE. Hope the codeforces team fixes this bug. MikeMirzayanov
Auto comment: topic has been updated by _chroneZ (previous revision, new revision, compare).
Fixed now. thx