Skip to main content

Timeline for Selling blocks of time slots

Current License: CC BY-SA 3.0

7 events
when toggle format what by license comment
Nov 22, 2016 at 17:45 comment added Chao Xu @j_random_hacker The cost of $s_iv_j$ would require that $s_i$ to be the $i$th person in the optimal solution.
Nov 22, 2016 at 17:39 comment added j_random_hacker @ChaoXu: I don't think so: in any assignment of blocks to people, the assignment can be listed in increasing order by person. (Notice that nothing forbids a person $i' > i$ being assigned a block ending at $j' < j$, where $j$ is the first block assigned to person $i$.) But I have a feeling that a close relative of the problem that affected my first attempt also affects this one...
Nov 22, 2016 at 17:37 comment added Chao Xu @j_random_hacker then you are forcing an ordering of the $k$ people.
Nov 22, 2016 at 17:30 history edited j_random_hacker CC BY-SA 3.0
Warn that there are problems.
Nov 22, 2016 at 17:29 comment added j_random_hacker @templatetypedef: I believe you're right; I'll delete this answer shortly. What about this construction instead: We have the same vertices and edges as before, but now we try to "thread" a single unit of flow through a "pipeline" of people (ordered by increasing $i$ value) by deleting all edges $ss_i$ except for $ss_1$ and all edges $t_it$ except for $t_kt$, and adding an edge $t_is_{i+1}$ with huge negative cost $-M$ for each $1 \le i < k$. The $-M$s will force the single unit of flow to visit all $k-1$ of these "pipeline" edges in any optimal solution.
Nov 22, 2016 at 16:28 comment added templatetypedef Might this fail if some person $i$ takes a route from their source to another person's sink and vice-versa?
Nov 22, 2016 at 13:09 history answered j_random_hacker CC BY-SA 3.0