Hi codeforces, I want to know the reason why in the right side we have a tag section claiming whether its a dp problem or tree or graph problem.That solves the whole fun of solving the problem.All these things should be in editorial of problem not visible when oyu freshly open a problem.What is CF communities points on this issue?

in question C round A of google code jam university round Jane's Flower Shop i saw peoples solution why have they assumed the irr function to be a decreasing function cant it be increasing function i am saying this because in most code of accepted solution i saw if(v < 0) hi = m; else lo = m; where v is the value of the function at m. link to question::https://code.google.com/codejam/contest/11274486/dashboard#s=p2

Yesterdy i solved 3 questions on round 360 div2.After the system test also the verdict passed was fine.then after 2 hours i came to check my rating much to my dissapointment the verdict had turned to skipped and i was not there in the competition charts what had happened how to avoid this in future Note:my friend had his codeforces account logged on earlier on my laptop so when i was subbmitting problem 1 i did on his account.realising this i logged out submitted the same solution from my account and did the rest 2 from my account.did submitting from friends account then mine resulted in cheating and system declared all my submissions invalid???

How to solve code jam Practice Round APAC test 2017 question 4 "sum of sums "using binary search".pls guys help me out link to the question:https://code.google.com/codejam/contest/5254486/dashboard#s=p3 does a segment tree solution to the problem exist pls elaborate a little bit cause i am a noob