Please note that regions of different phases can coexist in the wire. If regions of different phases emerge, the phase separation points on the wire start moving along the wire according to the direction of the net thermal flux. Since the thermalization time is short, we may assume that phase separation points will find and will follow the positions corresponding to a thermal quasi-equilibrium.
Please submit the solution to this problem via e-mail to physcs.cup@gmail.com. The next hint for the Problem 1 will be published at 13:00 GMT, 15th January 2023, together with the next updates of the intermediate results.