public Solution SolveBrute(char[,] board)
{
var changes = board.ToPoints().Where(p => board.Get(p) != 'o')
.Select(p => (board.Get(p) == '.' ? ".+xo" : board.Get(p) == 'o' ? "o" : (board.Get(p) + "o")).Select(c => new { c, p }).ToArray())
.ToArray();
var bestScore = 0;
var bestBoards = new List <char[, ]>();
foreach (var comb in CombinatoricsHelper.Selections(changes))
{
var resultBoard = board.ShallowClone();
foreach (var change in comb)
{
resultBoard.Set(change.p, change.c);
}
if (!IsBoardOk(resultBoard))
{
continue;
}
var score = Score(resultBoard);
if (score > bestScore)
{
bestScore = score;
bestBoards.Clear();
bestBoards.Add(resultBoard);
}
else if (score == bestScore)
{
bestBoards.Add(resultBoard);
}
}
return(new Solution {
Score = bestScore, Board = bestBoards.Count == 0 ? null : bestBoards[0]
});
}
