Is there a specific reason for having N = 10⁶ in the 3rd problem ? This makes it almost impossible to solve it in Java.

I had 2 submissions with 100% idential complexity, number of iterations, the one in Java gave me TLE, the one in C++ gave me AC.

In problem A, it seems OK to have a trailing space at the end of a list of numbers. Is this standard in Codeforces (i.e., trailing spaces are ignored)?

By the way, I LOVED, LOVED problem A. It looked sooo clear and simple but I just couldn't wrap my brain around it until the very end. It was really infuriating!! And even then I didn't end up with the intended solution which was really beautiful.

"Implementation problems" are often just a bunch of boring details. This one was a real gem!

I think this solution is wrong but it passed.

Another solution for problem D: - First, store all the cartons you can buy at the store in a vector and sort them non-increasing.

• Then, iterate all the possible dates from the biggest one down, store a value to keep track of the amount of cartons that needs to be drank in the current date. Let's call this value cur

• If at a certain moment, cur > 0, that means we have drank enough from this day forward. Update our answer using the vector of milk cartons. This can be done by using a pointer.

• Therefore, our total complexity is O(N log N + t)

For more details, here is the code

Hello, Can somebody please explain why my solution here receives a TLE, even if the solution complexity is the same as in the presented solution? Thank you :D

yay! :) Then I can consider my O(10⁷ + m) solution for D pretty good. :)

Solution for B: ~~~~~ ~~~~~

long min = 0;
        long mins = ts+t;
        int pl = 0;
        for (; pl<n; pl++) {
            if ((ts+(pl)*t+t<=tf) && (ts+(pl)*t+t-(mas[pl]-1)<mins))
            {
                mins = ts+(pl)*t+t-(mas[pl]-1);
                min = mas[pl]-1;
            }
        }
        System.out.println(min);

So easy...

Can anyone help me understand why my solution to problem D is getting TLE???. I am pretty sure complexity is O(10^7+n+m). Shouldn't it get accepted???

My solution

Please help me.....

Hello, could someone write more detailed explanation of C problem, I still don't understand how the second case works, even though I took a look at a couple of solutions and read the editorial.

Any help would be greatly appreciated, thanks!

Can somebody please help me in question C.I have created a tree and used recursive calls to find sum.Implementation is O(n) but still it gets time limit exceeded in Testcase 12. Please check my solution and tell me the problem please. Code is with proper comments. Thanks http://codeforces.me/contest/767/submission/24804939

The solution is much more simple that the author's. Do DFS from root node, and for every subtree, can calculate the total heat using regular tree DP. Then, when returning the value, if the total heat of subtree is equal to total heat of whole three / 3 then set to 0 in order to avoid double counting. Code explains the concept much better than words, in my opinion.
Code: 24764409

In problem C, Both cases can be handled by this —

While calculating sub tree sums, If you find a node with sub_tree_sum == sum/3 then do not add this sum to it's ancestors :) This will solve the first case as well as second case.

Now you just need to find just 2 such nodes :) Which can be done while calculating the sums. :) Needs ~10 lines of code :)

See this code — 24812043

In problem C, Both cases can be handled by this trick —

"While calculating sub tree sums, If you find a node with sub_tree_sum == sum/3 then do not add this sum to it's ancestors :D"
This will solve the first case as well as second case.

Now you just need to find just 2 such nodes :) Which can be memorized while calculating the sums. If if we can't find at least 2 such nodes then there is no solution.

My Code — 24812043