7.25 simulation summary

GA GA

It seems that the stomach is not so uncomfortable Is always diarrhea GA …

Today's list ：50 Divide anger and rush rank2

7.30-8.30

Look at the question I feel like I have no idea T1 Feeling is dp But not T2 Feeling is ds T3 Don't know much about

8.30-9.30

Thought about it for a while I hit T2 The violence of I feel that I can't use Cartesian tree （ The two-dimensional situation cannot be extended to three-dimensional ）

9.30-11.00

I hit T3 Two kinds of violence

11.00-12.30

Make it up T1 Chain approach Forced true greed compound dp And then go on thinking T2 It feels monotonous and difficult to do

Topic analysis

T1

Don't understand,

upd

This question （ Namely dp That kind of ） It's hard for me to order （ I want to transfer the corresponding ）

$f[x,op,op1]$ It means that $x$ In the subtree spot $x$ The state of is $op$ There are... In the subtree $op1$ Endpoints

At first, I didn't understand why 0 I stepped on it more $u$ 2 I stepped on it more v

Until I hit my watch later and found ： The endpoint that is not in the subtree by default At o'clock $x$ On

For example, a 12 13 The tree of $f[1,1,0]=12131$

T2

Don't understand! It feels like a Cartesian tree / Monotonic stack mixing

upd

consider $mnA,mnB$ Location taken Divide and conquer to do this thing

T3

It's just violence The difference is the number of the upper layer before the change point of the property is found Otherwise, it is the current layer number

upd：

Consider maintaining the long chain The point on the long chain has only one Son except the tail Then the answer can only be the inquiry point or the tail point of the long chain

Then consider the chairman tree to maintain this thing