caozhu

Beijing, China

Age: 24

I'm a fourth year undergraduate student in Tsinghua University.

Nov
20
comment Why is HAMILTONIAN CYCLE so different from PERMANENT?
I have a question a bit off the topic. May I ask why PERMANENT is in P over the boolean semiring? I'm not aware of such an algorithm.
Sep
24
awarded Autobiographer
Sep
24
awarded Autobiographer
Sep
24
awarded Autobiographer
Sep
24
awarded Autobiographer
Sep
24
awarded Autobiographer
Sep
24
awarded Autobiographer
Sep
24
awarded Autobiographer
Apr
22
awarded Popular Question
Mar
23
comment Extensions of Sylvester's inertia law?
The problem description is not at all clear. How is $n$ defined for example. And is all the coordinate of $M$ belongs to the same space so that $F$ can be well defined. A more precise formulation of the problem would be adding the condition that $M:R^n \times \dots \times R^n \to R$.
Feb
21
comment $NP$-completeness of recognizing the difference of two permutations
Why not ask Peter directly? @Peter
Feb
20
comment Crown Rule Reduction In Parameterized Complexity - Vertex Cover - Notion Question
From your description, I don't see any errors.
Feb
20
comment Sorting using read-only stacks
I don't think it's possible to print the sorted list given the allowed operations. According to the register machine model, the first entry printed must be one of the first element of some register. Thus if the smallest element is at the end of one register, we can't possibly print it out firstly as it should be.
Nov
19
awarded Popular Question
Jun
15
awarded Supporter
Jun
15
awarded Student
Jun
15
comment Finding a concave function that minimize the middle value while the boundary values are fixed
I think the condition is not exactly "concave function" which I'll check with Dominik. I would appreciate it if you can find some "concave-like" properties of the candidate function I gave, like concave for only a certain class of endpoints.
Jun
15
accepted Finding a concave function that minimize the middle value while the boundary values are fixed
Jun
14
revised Finding a concave function that minimize the middle value while the boundary values are fixed
added 90 characters in body; edited title
Jun
14
comment Finding a concave function that minimize the middle value while the boundary values are fixed
@hardmath:corrected, thx
1 2 3 4