delete

代码说明：

  删除数组中小于某个特定值的所有函数，或删除大于某个特定值的所有函数，或删除某一指定范围内的所有元素，用二叉树实现(Delete all functions in the array that are less than a particular value, or delete all functions that are larger than a particular value, or delete all elements within a specified range, with a binary tree)