please use c++ language to solve this question, and write comments in the code, thank you!

Here's the main function words.cpp:

#include

#include

#include

#include

#include "wordtree.h"

using namespace std;

int main() {

ifstream fin;

ofstream fout;

string filename;

cout

cin >> filename;

fin.open(filename.c_str());

if (fin.fail()) {

cout

exit(1);

}

cout

WordTree myTree;

// insert code here

fin.close();

fout.open("results.txt");

cout

cout

fout

cout

fout

cout

fout

fout.close();

return 0;

}