Mahjong is a puzzle game of matching tiles. Help to clear this confusing mess!! XD

There are many, many tiles with all kinds of pictures, but each picture always has an identical pair. The tiles are placed next and on top of each other to form a puzzle.

The rules to solve the puzzle are very simple, you have to pick two tiles, both of them not blocked from the left OR from the right by other tiles (so you can freely shift it to the left or to the right), and the tile must also not have anything on top of it, blocking it from above. So just select two identical tiles that satisfy this condition and they will be instantly removed from the board!

But since many tiles are blocked (can't be freely moved to the left or right), the question is what to remove first and what would be wiser to keep for later? There are always many forks and options in the strategy!