public void FindsFirstTarget()
{
var search = new AStarSearch <int>(EqualityComparer <int> .Default, InfiniteExpander);
var result = search.FindFirst(1, x => x == 192, GrowHeuristic);
Assert.AreEqual(1, result.Steps.First());
Assert.AreEqual(192, result.Steps.Last());
Assert.AreEqual(6, result.Length);
Assert.AreEqual(5 + 1.8, result.Cost, 1e-6f);
}
public override async ValueTask <string> Solve_1()
{
var dest = _grid.BottomRight;
var s = new AStarSearch <Point>(null, Expand);
var path = s.FindFirst(new Point(0, 0), x => x == dest, x => x.ManhattanDistTo(dest)) !;
var totalRisk = path.Cost;
return(totalRisk.ToString());
IEnumerable <(Point node, float cost)> Expand(Point p)
{
foreach (var n in _grid.Get4NeighborsOf(p))
{
yield return(n, _grid[n] - '0');
