Skip to content / Đến nội dung
ThichHocToan.com

MathNet 2022-part-02 — 197 problems (EN–VI) Question 115

Math Olympiad Vault · MathNet 2022-part-02 — 197 problems (EN–VI)

Question 115

Maena and Théodore play a game. They play on a square grid made of $99 \times 99$ cells. Two cells are considered adjacent if they share a vertex or a side.

Initially, Maéna numbers the cells of the grid from 1 to $99^{2}$, in an arbitrary way. Théodore then places a token on one of the cells of the square, and then allows himself moves of the following form: he may move the token from one cell to another only if these cells are adjacent and if the new cell on which the token lands has a strictly larger number than the old cell.

What is the minimum number of moves that Théodore can guarantee, whatever the way in which Maena has placed her integers?