2000A — Primary Task
Video
2000B — Seating in a Bus
Video
2000C — Numeric String Template
Video
2000D — Right Left Wrong
Video
2000E — Photoshoot for Gorillas
Video
2000F — Color Rows and Columns
Video
2000G — Call During the Journey
Video
2000H — Ksyusha and the Loaded Set
I initially solved this problem for a fixed value of k (by mistake), and then generalized it for varying values of k.
Video









Only video Tutorial?
how solutions with O(n*k*100*100) passes in F?
maybe the right solution is O(nk(a+b)).
Yes it's the intended solution but there are other solutions that passes with nk*10000
why in the last test in problem f the answer is 35 ? i tryed all the ways and the minimum is 36
Choose the whole first rectangle and the whole last rectangle and one column of the third rectangle. You will get 18 points in 35 moves.
The last cell contribute to the answer with 2 not 1 because you then color a row and a column in the same time so the greedy solution doesn't really work because its not globally optimal to just take the current smallest number.
Alright, I'm just gonna say it. This video tutorial is not very good. No offence to Shayan but this is not very helpful for someone who is just getting started. Wish we had a text editorial as well.
May i ask why you think it's not helpful? it's better for people to just focus on problems around your level, so it's common if you don't understand how to solve problems with rating above 1900 or 2000. Shayan did a great job on explaining the observation and the concept of problems which i think it's very helpful for beginner, not just about what algorithm/data structure we need to use.
And we will always have text editorial, it's just not out yet
I'm Chinese and I can't watch video on Youtube without VPN.
I am Syrian and in my country YouTube videos appear without ads, so you can change your region using a VPN to Syria
Thank you!
I'm Chinese too,so I agree with it.Word solutions might better.
thanks for the good work !
I participated in the contest and solved A,B,C, now it is my B and C are marked as red. Can anyone tell me why this happened?
System testing is going on. Your solution will be again judged on new added test cases thats why they are marked red. wait for sometime they will be evaluated
I need help
Can anyone tell me why my solution in proplem E got TLE when i write it in java , but when i write the same code in c++ i got AC
java solution --> Your text to link here...
c++ solution --> Your text to link here...
The video tutorial is good but I think the written editorial is the best.
can someone explain the last eg of tc1 in problem F?
Solution
Approach: Stored the loads available in a map of int, set. Key is load, and the set stores the values just after which the available series of a particular load starts.
For query "?" just find the load greater than or equal to the this value in the map and print the first element of this set.
For query "+" find the values just greater and less than this value, this will give the available load and the value just before the start of series. Now remove this value from that set, and calculate two different loads and insert them into the respective keys of the map.
For query "-" find the values just greater and less than this value, this will give two available loads, remove from those and insert into the new load.
Please explain what is wrong in the implementation or logic.
I did the same logic and it fails in the following case:
1
6
1 4 6 7 8 9
1
? 1
Answer is 2 but code give 5.
Could you please provide a solution tutorial in text? In computer classroom we are not allowed to play a video with sound, because it may disturb others.
Only vedio TUtorial?please NO!!!
https://mirror.codeforces.com/blog/entry/132689
Vladosiya
Please link it in the contest material I think most people didn't see it.
Oh, thanks
why does problem G have binary search tag?