Introduction - If you have any usage issues, please Google them yourself
Written to solve geometry perimeter, area of application requirements are as follows:
1) The geometry requires at least linear, triangular, rectangular, round and other types of computing perimeter, area, etc.
2) requires to calculate the distance between two graphs
3) requires two graphics performance computing Boolean operations (ie, pay, and, worse) after the area (for optional).
4) must use inheritance, interfaces, polymorphism, and packages