private static int Solution1(string[] input)
{
TargetArea targetArea = new(input[0]);
int xDirection = Math.Sign(targetArea.XFrom);
int minX = Math.Min(Math.Abs(targetArea.XFrom), Math.Abs(targetArea.XFrom));
int xVelocity;
for (xVelocity = 1; SequenceHelpers.TriangularNumber(xVelocity) < minX; xVelocity++)
{
}
Point initialVelocity = new(xVelocity * xDirection, Math.Abs(targetArea.YFrom) - 1);
(_, int height) = targetArea.WillProbeHit(initialVelocity);
return(height);
}
public void TriangularNumbers(int n, int expected)
{
int actual = SequenceHelpers.TriangularNumber(n);
Assert.Equal(expected, actual);
}
static int FuelCost(int n) => SequenceHelpers.TriangularNumber(n);