March Training 2

March 7

Today is the first day

My score: 0 Highest score: 230

T1

Simple DP, only I didn't do it.

Calculates the maximum answer for each subtrees tree that includes the K sub-node, the bare N3 DP.

But because the complexity of DP is not a state * shift, but sigma transfer complexity. So it can be proved that the complexity of this thing is actually N2.
L[i],r[i] represents the left and right sub-tree of the I point.
The following proofs: f[i]<0.5* (s[i]+1) ^2
The complexity of the leaf nodes after the preprocessing is calculated separately is 0 obviously established.
f[i]=f[l[i]]+f[r[i]]+ (s[l[i]]+1) * (s[r[i]]+1)
<0.5* ((s[l[i]]+1) ^2+ (s[r[i]]+1) ^2+2* (s[l[i]]+1) * (s[r[i]]+1))
=0.5* (s[l[i]]+s[r[i]]+2) ^2
=0.5* (s[i]+1) ^2

I didn't know how to read the question in the exam and felt very God and didn't do it. In short, you are too weak.

T2

Math problem.

Easy ans = Sigma{i=0..n3,i=kp+ri} binom (N1,i) *binom (n2,n3-i) *binom (n3,i)

Then according to the Lucas theorem direct violence can be 30 points.

T3

Bare Point Division to maintain a trie.

Consider using Trie to maintain the existence of a number if the binary of the tree can come out on the Trie to indicate that it exists.

Consider using Trie to find a number in a heap number in the same or the largest number, only need to be able to walk the opposite side of the Trie in the opposite side and the statistics or value plus this bit, otherwise walk the same side, go to the end is the answer.

It's a clever practice I haven't seen before but everyone else has seen a lot of sides, which means that I do too few questions.

And then the point division is naked. There is nothing to say, it is worth noting that when dealing with a node as the root of the time to take it all the son of the first to sweep one side and sweep again, in order to update the correct answer.

The title of the game is not difficult, but my 0 points expose a lot of problems I have to face them.

From two days ago the completion of the CCC and then to the explosion here 0, the previous period of time also naïve to believe that their own getting better until the bloody facts in front of me ripped, really uncomfortable.

But now the only response is to cheer up, in a more serious way to do more problems, summed up their failure.

His current code ability is not to come to cry to death. Coping measures: More dozen write the disgusting data structure problem to hit some yards farming problem.

Always feel that their pay did not get the same amount of return, but I should contact me in the half-hearted when doing the problem, often on their own perfunctory.

If even oneself all perfunctory to oneself, still have who, what thing will repay me, will attach importance to me.

I believe that all the great gods have been abused all the way from me, and there is always no life down that will abuse people t^t

I believe I will be able to smooth out the trough period to gain the ability of breakthrough!

So many people believe in me, I have no reason not to believe in themselves. Believe that you have the talent, believe that you can work harder.

Things to do these days:

I did all the questions that Jiry_2 's blog had.

March Training 2