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-1 votes
3 answers
84 views

An Optimization Problem With Permutation Function [closed]

When I tried to solve an one-to-one assignment problem, I constructed it as the following optimization problem, which is a min-max optimization problem with the optimization objective being functions. ...
Jiayu Zou's user avatar
0 votes
0 answers
8 views

Bipartite Matching With Distant Constraints

I am investigating the complexity of the following problem. Let a complete bipartite graph $G = (V \cup V', E: V \times V')$ with |V| < |V'|, where the nodes have weights $w: V \cup V' \to \mathbb{...
Dom's user avatar
  • 9
3 votes
1 answer
62 views

Greedy lemma Problem for matching spears to soldiers

The problem has $n$ spears and $n$ soldiers. Spears and soldiers have heights. We want to assign spears to soldiers such that the total height difference of spears and their assigned soldiers is ...
Yavuz Bozkurt's user avatar
2 votes
0 answers
51 views

Prove that $P_{\text {match }}(G) \cap\left\{x: 1^T x=k\right\}$ is the convex hull of all matchings in $G$ of size exactly $k$.

Problem: Prove that $P_{\text{match}}(G) \cap\left\{x: 1^T x=k\right\}$ is the convex hull of all matchings in $G$ of size exactly $k$. My attempt: Firstly, we prove that $$\text{conv}\left\{\chi_M: M ...
Tung Nguyen's user avatar
  • 1,238
2 votes
1 answer
100 views

Maximise $\sum_{x,y\in S} GCD(x,y)$ where $S = \{1,2,\ldots, 100\}$ and each number appears once in the sum

Question: One day Anindya and his friend Faria cooperated to play a fun game. They played to maximize the sum of points they gained throughout the game. Let $S = \{1,2,\ldots, 100\}$. There are $50$ ...
user avatar
2 votes
1 answer
50 views

Understanding the proof perfect matching polytope

Theorem. Let $M$ and $N$ be perfect matchings in a graph $G=(V, E)$. Then $\chi^M$ and $\chi^N$ are adjacent vertices of the perfect matching polytope if and only if $M \triangle N$ is a circuit. ...
ohana's user avatar
  • 873
1 vote
1 answer
62 views

Understanding the proof of Konig edge-colouring theorem

Theorem: (König's edge-colouring theorem). For any bipartite graph $G=(V, E)$, $$ \chi(G)=\Delta(G) . $$ That is, the edge-colouring number of a bipartite graph is equal to its maximum degree. Proof. ...
ohana's user avatar
  • 873
2 votes
0 answers
116 views

Prove that symmetric difference of two perfect matchings is union of disjoint even cycles

Problem: Let $M$ and $N$ be perfect matchings of a finite graph $G$. Prove that their symmetric difference is a union of disjoint even cycles. My attempt: Firstly, if $M = N$, we are done. Now, let us ...
Tung Nguyen's user avatar
  • 1,238
0 votes
0 answers
55 views

Is there a way to do the Hungarian algorithm in reverse?

The Hungarian algorithm is used to find the optimal choices for a given 'cost matrix' e.g. going from the output of the Hungarian algorithm ...
Machai's user avatar
  • 1
1 vote
0 answers
56 views

Hungarian Algorithm Adjustment Step

I am not sure whether I can simply not find an answer or I am just missing something obvious, but there is a step in the Hungarian algorithm which I am having trouble understanding; I will be ...
Thaloukos's user avatar
1 vote
1 answer
219 views

How to modify the hungarian algorithm for bipartite graphs with multiple edges with some already imposed connections

The Hungarian algorithm can be seen to take as input a complete weighted bipartite graph and outputs an optimal matching, maximising or minimising the sum of all the edges. Crucially, this algorithm ...
Emil Sinclair's user avatar
1 vote
0 answers
55 views

Finding a min weight matching of a specific size

For a complete graph $G=(V,E)$, i want to find a minimim weighted matching of a size $n$ where $n \leq \lvert V \rvert$ is there any known algorithms for such a problem other than IP formulations?
Magnus M's user avatar
  • 121
2 votes
1 answer
98 views

Points on a circle with maximum pairwise distance

We are given $n$ points on a circle of radius $1$ and an even number $k$. The distance $d(x,y)$ between two points $x$ and $y$ on the circle is given by the length of the (shorter) arc connecting them ...
reservoir's user avatar
1 vote
2 answers
180 views

Pairing cartesian coordinates for minimum distance

I have n start locations, defined by their x,y coordinates on a two-dimensional plane. I have a further n destination locations (again, as x,y coordinates) that differ from the start locations. All ...
Okanagan's user avatar
1 vote
1 answer
20 views

How to assign a known number of different size of outbound packages, to a known (different) number of inbound deliveries?

I am trying to solve a problem that looks like the multiple knapsack problem, the multiple bin packing problem and the subset-sum problem, but isn't exactly one of them. Imagine a warehouse where 4 ...
FabRice's user avatar
  • 13

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