diff --git a/main.pdf b/main.pdf index 89a64e9..3ce7d82 100644 Binary files a/main.pdf and b/main.pdf differ diff --git a/main.tex b/main.tex index 415393b..0e9c6b3 100644 --- a/main.tex +++ b/main.tex @@ -105,7 +105,7 @@ where the second inequality uses \autoref{lem:conditionalLB}. One can see that if $\alpha>2$, $\frac{w(C^N\setminus F^N)}{w(C^*\setminus F^*)}\leq \frac{B}{\alpha B-b} <1$ which implies $(C^*,F^*)$ is not optimal. Thus for $\alpha >2$, $X^*$ must be a $2$-approximate solution to $\min_{X\in\mathcal F} w_\tau(X)$. Finally we get a knapsack version of Theorem 4: -\begin{theorem}[Theorem 4 in \cite{vygen_fptas_2024}] +\begin{theorem}[Theorem 4 in \cite{vygen_fptas_2024}]\label{thm:main} Let $X^{\min}$ be the optimal solution to $\min_{X\in\mathcal F} w_\tau(X)$. The optimal set $X^*$ in \autoref{bfreeknap} is a 2-approximation to $X^{\min}$. @@ -254,7 +254,7 @@ We want to prove something like tree packing theorem for \autoref{lp:dualcutint} I believe the previous conjecture is not likely to be true. -\paragraph{Weight truncation} Assuming we know the optimal $\lambda$ to the LP dual, \autoref{lp:dualcutint} in fact gives the idea of weight truncation. The capacity of each edge $e$ in the ``tree packing'' is $\min\{c(e)\lambda,w(e)\}$. Therefore, the optimum of \autoref{lp:dualcutint} is $\Lambda_{w_\tau}-b\lambda$, where $\Lambda_{w_\tau}$ is the fractional mincut on $G$ with weights $w_\tau$. +\paragraph{Weight truncation} Assuming we know the optimal $\lambda$ to the LP dual, \autoref{lp:dualcutint} in fact gives the idea of weight truncation. The capacity of each edge $e$ in the ``tree packing'' is $\min\{c(e)\lambda,w(e)\}$. Therefore, the optimum of \autoref{lp:dualcutint} is $\Lambda_{w_\tau}^{fr}-b\lambda$, where $\Lambda_{w_\tau}^{fr}$ is the fractional mincut on $G$ with weights $w_\tau$. \paragraph{The optimal $\lambda$} Denote by $\lambda^*$ the optimal $\lambda$ that maximizes $L(\lambda)$. From the previous argument on the first segment of $L(\lambda)$ we know that $\lambda^* \geq \min \frac{w(C\setminus F)}{B-c(F)}$. Now assume $\lambda^* > \min_{c(F)\leq b} \frac{w(C\setminus F)}{b-c(F)}$. We have $\min w(C\setminus F)-\lambda^*(b-c(F))