python 3.8.2
This app solves a puzzle I found in mobile game called "Water Sort Puzzle".
You have several vials of the same size, some of them filled with colored water. The water of different colour could be stacked in one vial, but it not mixes.
You start with several vials that contains colored water and some (one or two) empty vials. The water in each vial different coloured and stacked on each other. The goal is to sort all water in vials, so every vial should end up with only one colour or be empty.
In one step you can move only water that's on the top of vial. You can put this water only to the same colour or to the empty vial. If donor vial contains several layers of water of one color, all the layers will be moved to destination vial until it's full.