v2.10

• Changed how hints are displayed. They will also be remembered in case the user undoes a move and a hint was calculated for that previous move at some point before.
• Small performance improvements of all solving algorithms.

v2.9

• Added the ability to ask the computer for a hint while playing the game.
• Improved performance of all solving algorithms.

v2.8

• Made -lessMemory the standard behavior when when solving game boards. As such it is not necessary to use that program parameter anymore.
• Renamed -lessMemoryQueueCutoff to -queueCutoff. Although the latter is preferred, -lessMemoryQueueCutoff will continue to work.
• Performance of the solving algorithms got very slightly worse for problemsets with non-heavy memory requirements, but improved a decent amount for problemsets with larger memory workloads.

v2.7

• Improved performance of all solving algorithms, mainly during memory heavy workloads where it makes sense to use -lessMemory or -lessMemoryQueueCutoff memory schemes.

v2.6

• Improved performance of all solving algorithms, mainly when using the -lessMemory and -lessMemoryQueueCutoff memory schemes.

v2.5

• Improved performance of astar_ias and astar_ia.
• -lessMemoryQueueCutoff now needs more time to solve boards but tends to find better solutions.

v2.4

• Improved the performance of all solving algorithms by a sizeable degree.

v2.3

• Fixed a bug with -lessMemory and -lessMemoryQueueCutoff modes that could rarely result in worse solutions being found.
• Slightly improved performance of all solving algorithms.

v2.2

• Added memory saving modes. They can be used with the parameters -lessMemory or -lessMemoryQueueCutoff when trying to programmatically solve game boards. See the documentation for details.

v2.1

• You can end the game by typing exit or quit.
• Slightly improved performance of the astar_a strategy.