English

Greedy Gossiping

Combinatorics 2025-06-24 v1

Abstract

The renowned Gossiping Problem (1971) asks the following. There are nn people who each know an item of gossip. In a telephone call, two people share all the gossip they know. How many calls are needed for all of them to be informed of all the gossip? If n4n\ge 4, the answer is 2n42n-4. We initiate and solve the related Greedy Gossiping Problem: given a fixed number m<2n4m<2n-4 of calls, at most how much gossip can be known altogether? If every call increases the total knowledge of gossip as much as possible, the sum reaches n2n^2 only when m=2n3m=2n-3. Our main result is that surprisingly, for each m<2n4m<2n-4, this calling strategy is optimal.

Cite

@article{arxiv.2506.17804,
  title  = {Greedy Gossiping},
  author = {Kada Williams},
  journal= {arXiv preprint arXiv:2506.17804},
  year   = {2025}
}
R2 v1 2026-07-01T03:28:00.369Z