Colorstacks is a logistic puzzle with 7 levels.
The game consists of columns with colored blocks.
The lowest block depicts the color of the column. This block is fixed.
The other blocks may move, one or two at the time, to another column.
Rule is that only blocks of the same color may rest on each other.

In the starting position a column anly contains blocks of "foreign" colors.
In the final, solved, position each column only contains blocks of it's own color.
    starting position of level 3solution of level 3


    - search for solutions
      - move blocks using the mouse
      - take moves back
      - restore game to starting position

    - replay earlier solutions
    - have the computer search for solutions
    - save a solution on disc
    - open a solution from disc
    - print a solution


The program has in-line help information.

It is written for Windows in the Delphi (7) programming language.
There is no installation procedure: simply copy colorstacks.exe to a map of choice.

Download Colorstacks by clicking on the (lightning) icon at the top of this page.

The search algorithm

I do not know of an analytical approach of this puzzle.
But I feel that there must be one.
The computer uses the "brute force" (systematically try all move sequences) method to find solutions.
To limit the search time however, a number of trics are applied to avoid redundant work.
Solutions of level1 1..6 are found by the computer in (milli) seconds.
For level 7 however I feel that the shortest solution has not yet been found.