This number puzzle - Number Klotski is a variant from the traditional Klotski puzzle, it may be addictive, please use it with caution, take a rest when you feel it is needed.

The rule is relatively simple:
1. There is only one empty square.
2. Every other blocks were assigned a unique number.
3. Each time, only one block or few continous blocks could be moved torwards the empty square.
4. The goal is to arrange the blocks in numerical order, from left to right, from top to bottom.

The challenge ranges from 3 x 3 to 9 x 9, be patient with the final 9 x 9.

The challenge is not only about finding the correct sequence of moves, but also in doing so with the least number of moves.
It requires strategic planning, problem-solving, and patience.

* History of Klotski Puzzle
The Klotski puzzle is a captivating sliding block puzzle with a rich history that has been enjoyed for centuries as a form of entertainment and mental stimulation.

The Klotski puzzle is believed to have originated in the early 20th century, although some sources suggest that it may be even older.