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Let
be an integer. Two players, Alice and Bob, play the following game on the complete graph
: They take turns to perform operations, where each operation consists of coloring one or two edges that have not been colored yet. The game terminates if at any point there exists a triangle whose three edges are all colored.
Prove that there exists a positive number
, Alice has a strategy such that, no matter how Bob colors the edges, the game terminates with the number of colored edges not exceeding
![\[
\left( \frac{1}{4} - \varepsilon \right) n^2 + n.
\]](//latex.artofproblemsolving.com/a/9/c/a9cca00e87c643af32eb75a2501b59060f3504fb.png)


Prove that there exists a positive number

![\[
\left( \frac{1}{4} - \varepsilon \right) n^2 + n.
\]](http://latex.artofproblemsolving.com/a/9/c/a9cca00e87c643af32eb75a2501b59060f3504fb.png)
This post has been edited 1 time. Last edited by EthanWYX2009, Mar 29, 2025, 2:56 PM