Problem

Source: Iran TST2 Day1 P2

Tags: combinatorics, 2020, game



Alice and Bob take turns alternatively on a $2020\times2020$ board with Alice starting the game. In every move each person colours a cell that have not been coloured yet and will be rewarded with as many points as the coloured cells in the same row and column. When the table is coloured completely, the points determine the winner. Who has the wining strategy and what is the maximum difference he/she can grantees? Proposed by Seyed Reza Hosseini