#include <fstream>
#include <cstddef>
#include <iostream>
#include <string>

using namespace std;
struct WordType
{
public:
  string word;
  int count;
};

struct TreeNode
{
  WordType info;
  TreeNode* left;
  TreeNode* right;
};

class ListType
{
public:
  ListType();
  void InsertOrIncrement(string letters);
  void PrintList(ofstream&);
private:
  TreeNode* root;
};

string GetString(ifstream&);    
const int MAX_LETTERS = 20;
int main()
{
  ListType list;
  string inFileName;
  string outFileName;
  string outputLabel;
  ifstream inFile;
  ofstream outFile;
  string letters;
  int minimumLength;
  
  // Prompt for file names, read file names, and prepare files
  cout << "Enter name of input command file; press return." << endl;
  cin  >> inFileName;
  inFile.open(inFileName.c_str());
  if (!inFile)
    cout << "file not found";

  cout << "Enter name of output file; press return." << endl;
  cin  >> outFileName;
  outFile.open(outFileName.c_str());

  cout << "Enter name of test run; press return." << endl;
  cin  >> outputLabel;
  outFile << outputLabel << endl;

  cout << "Enter the minimum size word to be considered." << endl;
  cin >> minimumLength;
  
  // Read the text stripping of words and inserting them into
  // list.  If a word is already there, its count is incremented.
  letters = GetString(inFile);
  while (inFile)
  {
	if (letters.length() >= minimumLength)
	  list.InsertOrIncrement(letters);  
	letters = GetString(inFile);
  }

  list.PrintList(outFile);
  outFile.close();
  inFile.close();
  return 0;
}

string GetString(ifstream& inFile)
// Post: Non alphanumeric characters as skipped. Alphanumeric characters are 
//       read and concatenated on a string until a non-alphanumeric character is
//       read or end of file is reached. Letters are all converted to lowercase.
{
  char letter;
  string letters = "";  
  
  inFile.get(letter);
  while (inFile && !isalnum(letter))
    inFile.get(letter);
  
  if (!inFile)	
    // No legal character found; empty string returned.
     return letters;
  else
  {// Read and collect characters.
    do
    {
	  letter = tolower(letter);
      letters = letters + letter;
      inFile.get(letter);
    } while (isalnum(letter) && inFile);

  }
  return letters;
}


ListType::ListType()
{
  root = NULL;
}
  

void Process(TreeNode*& tree, std::string letters)
{
  if (tree == NULL)
  {
    tree = new TreeNode;
    tree->info.word = letters;
    tree->info.count = 1;
    tree->left = NULL;
    tree->right = NULL;
  }
  else if (tree->info.word == letters) 
    tree->info.count++;
  else if (tree->info.word > letters)
    Process(tree->left, letters);
  else 
    Process(tree->right, letters);
}

void ListType::InsertOrIncrement(string letters)
{
  Process(root, letters);
}  
 
  
void Print(TreeNode*& tree, ofstream& outFile)
{
  
  if (tree != NULL)
  {
    Print(tree->left, outFile);
    outFile << tree->info.word;
    outFile  << " " << tree->info.count;
	outFile << endl;
    Print(tree->right, outFile);
  }
}

void ListType::PrintList(ofstream& outFile)
{
  Print(root, outFile);
}