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Peter and Bob

Source: All Russian 2014 Grade 11 Day 1 P2

April 30, 2014
combinatorics proposedcombinatorics

Problem Statement

Peter and Bob play a game on a n×nn\times n chessboard. At the beginning, all squares are white apart from one black corner square containing a rook. Players take turns to move the rook to a white square and recolour the square black. The player who can not move loses. Peter goes first. Who has a winning strategy?