Gathering all functions in a function then calling it in main function

#include <iostream>
#include <cstdlib>
#include <ctime>
#include <string>
using namespace std;

// Global stuff
const int tries = 3;

// Forward declarations
int letterFill(char, string, string & );
void MyFunction();

//
// Here the new slim main function 
//
int main() {
  // Call here MyFunction
  MyFunction();
  return (0);
};

//
// The 'ousourced' code
//
void MyFunction() {
  char letter;
  int wrong_guesses = 0;
  string word;
  string words[] = {
    "punjab",
    "balochistan",
    "sindh",
    "KPK",
    "NWFP"
  };
  //select random word from array and replace all of it's characters with *
  srand(time(NULL));
  int n = rand() % 5;
  word = words[n];
  string unknown(word.length(), '*');
  //game body that will show in output
  cout << endl;
  cout << "Hangman Game";
  cout << "\n\nYou have " << tries << " tries to try and guess the word." << endl;
  // Loop until the guesses are used up
  while (wrong_guesses < tries) {
    cout << unknown;
    cout << "\n\nGuess a letter: ";
    cin >> letter;
    // Fill secret word with letter if the guess is correct, otherwise increment the number of wrong guesses.
    if (letterFill(letter, word, unknown) == 0) {
      cout << endl << "wrong guess" << endl;
      wrong_guesses++;
    } else {
      cout << endl << "letter found. Find other letters." << endl;
    }
    // Tell user how many guesses has left.
    cout << "You have " << tries - wrong_guesses;
    cout << " guesses left." << endl;
    // Check if user guessed the word.
    if (word == unknown) {
      cout << word << endl;
      cout << "Congrats! You won the Game";
      break;
    }
  }
  if (wrong_guesses == tries) {
    cout << "\nSorry, you lose...you've been hanged." << endl;
    cout << "The word was : " << word << endl;
  }
  cin.ignore();
  cin.get();
}

/* Take a one character guess and the secret word, and fill in the
unfinished guessword. Returns number of characters matched.
Also, returns zero if the character is already guessed. */
int letterFill(char guess, string secretword, string & guessword) {
  int i;
  int matches = 0;
  int len = secretword.length();
  for (i = 0; i < len; i++) {
    // Did we already match this letter in a previous guess?
    if (guess == guessword[i])
      return 0;
    // Is the guess in the secret word?
    if (guess == secretword[i]) {
      guessword[i] = guess;
      matches++;
    }
  }
  return matches;
}