public int GetNextValue()
{
var coordinates = GetNextCoordinate();
var nextPoint = new SpiralGridPoint()
{
index = _spiralGrid.Count,
x = coordinates.Item1,
y = coordinates.Item2
};
var adjacent = GetPriorAdjacentPoints(nextPoint);
var sum = adjacent.Sum(p => p.value);
nextPoint.value = sum;
_spiralGrid.Add(nextPoint);
return(sum);
}
private IEnumerable <SpiralGridPoint> GetPriorAdjacentPoints(SpiralGridPoint point)
{
return(_spiralGrid.Where(p => p.index < point.index &&
Math.Abs(point.x - p.x) <= 1 &&
Math.Abs(point.y - p.y) <= 1));
}
