I added then removed the code to keep track of moves as chars, it was buggy. I added the last 2 test games. Game 1 & 2 can be solved with MAX_DEPTH=5 and ACE_DEC = 20. Game 3 can be solved with MAX_DEPTH=4 and ACE_DEC=0. By playing with these 2 parameters you can solve all 5 games I am sure.