MathDB
Moving shapes to form polygon

Source: 43rd International Tournament of Towns, Junior A-Level P2, Fall 2021

February 18, 2023
combinatoricsTournament of Towns

Problem Statement

On a table there are all 8 possible horizontal bars 1×31\times3 such that each 1×11\times1 square is either white or gray (see the figure). It is allowed to move them in any direction by any (not necessarily integer) distance. We may not rotate them or turn them over. Is it possible to move the bars so that they do not overlap, all the white points form a polygon bounded by a closed non-self-intersecting broken line and the same is true for all the gray points?
Mikhail Ilyinsky