//function used to perform simulation of the MCTS cycle
private int Simulation(MonteCarloNode _nodeToSimulate)
{
//sets the turn number to the enemy value, so that the simulation begins within the right turn
int _turn = MonteCarloBoard._enemyVal;
//creates a temporary node, setting the values to that of the node to simulate
MonteCarloNode _tempNode = new MonteCarloNode(_nodeToSimulate);
//creates a tempporary state, setting the values to that of the temporary node's state
MonteCarloState _tempState = _tempNode.GetState();
//checks for the current board status of the temporary node
int _boardStatus = _tempState.GetBoard().CheckStatus();
//checks if the current board state produces a win for the player
if (_boardStatus == MonteCarloBoard._playerVal)
{
//sets the score of the temp node's parent's state to the minimum integer value
_tempNode.GetParent().GetState().SetScore(int.MinValue);
//returns the board status value
return(_boardStatus);
}
//loops while the board state is in progress
while (_boardStatus == MonteCarloBoard._inProgress)
{
//changes the turn between the player and the enemy
_turn = 3 - _turn;
//performs a random play from the current tempstate
_tempState.randomPlay(_turn);
//sets the board status to the current board state of the temp state board
_boardStatus = _tempState.GetBoard().CheckStatus();
}
//returns the board status value
return(_boardStatus);
}
//function that returns all legal states available for current action
public List <MonteCarloState> GetLegalStates()
{
//creates a list to store the legal states
List <MonteCarloState> _legalStates = new List <MonteCarloState>();
//creates a list to store all legal positions and stores it with all legal positions returned from a function
List <MonteCarloPosition> _legalPositions = this._board.GetLegalPositions(MonteCarloBoard._enemyVal);
//loops through each position in the legal positions list
foreach (MonteCarloPosition _p in _legalPositions)
{
//creates a new state with the current board
MonteCarloState _newState = new MonteCarloState(this._board);
//performs the enemy action within the new state
_newState.GetBoard().performEnemyMove(_p);
//adds the new state to the list of legal states
_legalStates.Add(_newState);
}
return(_legalStates);
}
public MonteCarloState(MonteCarloState _state)
{
this._board = new MonteCarloBoard(_state.GetBoard());
this._visits = _state.GetVisits();
this._score = _state.GetScore();
}