Hi Codeforces
The ELO rating system seems to be unfunctional.
For an instance shokouf whose rate is 1640 , just recived +20 on a Div 2 contest in which he got 1586 th.
That seems pretty illogical compared to previous rating changes that CF had.
please write down your opinions :)

write down the problem that you get the most WA on it

except Water melon :))

comment your opinion down that what topic and tags is important for getting high rates in contests