Two drivers on a circular highway
Source: Kvant Magazine No. 4 2022 M2697 (appeared on the 24th Kolmogorov Memorial Cup)
March 8, 2023
Kvantcombinatorics
Problem Statement
There are some gas stations on a circular highway. The total amount of gasoline in them is enough for two laps. Two drivers want to refuel at one station and starting from it, go in different directions, both of them completing an entire lap. Along the way, they can refuel at other stations, without necessarily taking all the gasoline. Prove that drivers will always be able to do this.Proposed by I. Bogdanov