how to make a universal btree key

ackage bplustree import java.util.* import com.xuedi.IO.* import com.xuedi.maths.* ////// DisposeRoot ///////中的key参数有些问题 public class BTree {

B-Tree of order 4 Each node has at most 4 pointers and 3 keys, and at least 2 pointers and 1 key. Insert: 5, 3, 21, 9, 1, 13, 2, 7, 10, 12, 4, 8 Delete: 2, 21, 10, 3, 4