用c++编写：
The following represents a sample tree saved in a file.

The children of each node has an extra '\t'

at the beginning and the children of each

node are directly under it.

The tree can be very deep and each node can have 0 to many child nodes.

===========================

Root

V:\

FolderX

FolderA1

FolderD2

FolderB

FolderW1

FolderB2

D:\

FolderM

FolderQ1

FolderC2

============================

Please implement a program to load the whole tree into the memory from the tree file. The program should not only load the tree file above, but also load other similar tree files.

The tree data structure should be similar as.

Class Tree

{

string name;

int level; // the depth of the node from the root

Array children; // each object in the Array is the type Tree.

}

And then sort the child nodes of each node in the ascending order using IComparer interface.

Then print the tree out in the same tree file format