对北京大学，大连理工大学，浙江大学等五所高校的GPA算法进行一个比较，找出那个更合理。,Of Peking University, Dalian University of Technology, Zhejiang University and other colleges and universities 5 GPA algorithm a comparison to find out that more reasonable.

File input for making a Btree sructure. and then, you can insert your own nodes, and either can delete the nodes. this is practicing source, so student number and gpa are randomly generate.