public string PartTwo()
{
var N = 1000000;
var cups = new int[N];
var highestCup = CupLabels.Max();
for (var i = 0; i < N; i++)
{
if (i < highestCup)
{
cups[i] = CupLabels[i];
}
else
{
cups[i] = i + 1;
}
}
var cupCircle = new CupCircle(cups);
PlayNMoves(cupCircle, N * 10, cupCircle.CupWithLabel(CupLabels[0]), N);
var cup1 = cupCircle.CupWithLabel(1).Next;
var cup2 = cup1.Next;
var result = (Int64)cup1.Label * (Int64)cup2.Label;
return(result.ToString());
}
private void PlayNMoves(CupCircle cupCircle, int nMoves, Cup firstCup, int highestCupLabel)
{
var cup = firstCup;
for (var move = 0; move < nMoves; move++)
{
var pickedUpCups = cupCircle.PickUpNextThreeCups(cup);
var pickedUpLabels = new int[3];
var currentCup = pickedUpCups;
for (var i = 0; i < 3; i++)
{
pickedUpLabels[i] = currentCup.Label;
currentCup = currentCup.Next;
}
var destination = cup.Label > 1 ? cup.Label - 1 : highestCupLabel;
while (pickedUpLabels.Contains(destination))
{
destination = destination > 1 ? destination - 1 : highestCupLabel;
}
var destinationCup = cupCircle.CupWithLabel(destination);
cupCircle.PlaceCupsAfter(pickedUpCups, destinationCup);
cup = cup.Next;
}
}
public string PartOne()
{
var cupCircle = new CupCircle(CupLabels);
PlayNMoves(cupCircle, 100, cupCircle.CupWithLabel(CupLabels[0]), CupLabels.Max());
var cup = cupCircle.CupWithLabel(1);
var labels = "";
for (var i = 0; i < CupLabels.Length - 1; i++)
{
cup = cup.Next;
labels += cup.Label.ToString();
}
return(labels);
}