In these puzzles, you can pick up a block and drag it somewhere so that it doesn't overlap other blocks.
Your goal is to reach a particular position with a particular block.
These puzzles are made using Macromedia Flash, I assume
you will be automatically directed if you don't have the plugin.
The counter doens't count jumps with 1x1 blocks, that's because, since they can always be placed on every empty space, their only use is to adjust the number of empty spaces.
My program works with the number of empty spaces. That's why 1x1 blocks were not used in the position tree.