How many years has Tangram been in the history of China?

Perhaps the history of Tangram can be traced back to the ancient book "The Book of Changes Bisuan Classic" in China before Qin Dynasty, in which there is a tangent square, which is used to prove the Pythagorean theorem. At that time, the big square was cut into four identical triangles and a small square, not a puzzle. The present jigsaw puzzle has experienced a historical evolution. It developed from Yan Ji Tu in Song Dynasty to Die Ji Tu in Ming Dynasty, and then to Qiao Qi Tu in early Qing Dynasty. It has a history of more than 2500 years.