常用的算法经典代码，包括快速排序，冒泡排序等各种排序方法，还有二叉树的前序、中序和后序遍历等-The classic algorithm code, including quick sort and bubble sort sorting methods, as well as the preamble of the binary tree, inorder and postorder traversal, etc.

it is very useful for designing lms and wigner function and choes distribution functio inorder to remove the cross terms in the wigner function