How many shapes are there in a jigsaw puzzle?

The tangram puzzle is an old traditional Chinese intellectual toy, which, as the name suggests, is made up of seven boards. And these seven boards can be put together into many shapes (more than 1600 kinds), such as: triangles, parallelograms, irregular polygons, players can also put it into various characters, images, animals, bridges, houses, towers, etc., and can also be some Chinese and English letters.

The tangram is an invention of the ancient Chinese working people, whose history can be traced back to at least the first century B.C., and was basically finalized in the Ming Dynasty. Ming and Qing dynasties in China's folk widely circulated, Qing Lu to _ "Cold Lodge Miscellany" Volume I wrote: recent and seven tangrams, its style five, the number of seven, the change of its style more than to more than a thousand. The body is like a shape, with the hands of change, cover the game of tools, enough to row boredom break silence, so the world are happy to be.

In the 18th century, the tangram spread abroad. Joseph Lee said it is one of the oldest pastimes in the East, the library of the University of Cambridge in the United Kingdom also treasures a "new spectrum of seven coins".