private void Solve()
{
try
{
pnlChess.Visible = false;
pnlChess.Controls.Clear();
if (txtN.Text == "")
{
MessageBox.Show("Enter a valid number");
return;
}
var numberOfQueens = int.Parse(txtN.Text);
if (numberOfQueens < 4)
{
MessageBox.Show("Enter a number greater than or equals to 4");
return;
}
var board = new AStarBoard(numberOfQueens);
var stopWatch = new Stopwatch();
stopWatch.Start();
var result = AStarSearch(board);
stopWatch.Stop();
if (result != null)
{
pnlChess.Visible = true;
result.ShowBoard(pnlChess);
}
else
{
MessageBox.Show("No Result");
}
}
catch
{
MessageBox.Show("Error occured while trying to solve the NQueen Problem.");
}
}
AStarBoard AStarSearch(AStarBoard board)
{
if (board.IsGoal())
{
return(board);
}
else
{
for (var i = 0; i < board.NumberOfQueens; i++)
{
if (board.IsSafe(i))
{
board.Place(i);
var result = AStarSearch(board);
if (result != null)
{
return(result);
}
board.UnPlace();
}
}
}
return(null);
}