private static void RunCupGame(Dictionary <int, LoopedListNode> nodeDictionary, LoopedListNode start, int max, int iterations)
{
LoopedListNode targetNode;
LoopedListNode current = start;
LoopedListNode removed;
for (int i = 0; i < iterations; i++)
{
removed = current.next;
current.next = current.next.next.next.next;
int targetValue = current.value;
do
{
targetValue--;
if (targetValue == 0)
{
targetValue = max;
}
}while (removed.value == targetValue || removed.next.value == targetValue || removed.next.next.value == targetValue);
targetNode = nodeDictionary[targetValue];
removed.next.next.next = targetNode.next;
targetNode.next = removed;
current = current.next;
}
}
public Day23() : base(23, 2020, "")
{
Dictionary <int, LoopedListNode> nodeDictionaryOne = new Dictionary <int, LoopedListNode>();
Dictionary <int, LoopedListNode> nodeDictionaryTwo = new Dictionary <int, LoopedListNode>();
LoopedListNode firstNodeOne = null;
LoopedListNode firstNodeTwo = null;
LoopedListNode lastNodeOne = null;
LoopedListNode lastNodeTwo = null;
StringToNodes(Input, nodeDictionaryOne, out firstNodeOne, out lastNodeOne);
StringToNodes(Input, nodeDictionaryTwo, out firstNodeTwo, out lastNodeTwo);
RangeToNodes(10, 1000000, nodeDictionaryTwo, lastNodeTwo, out lastNodeTwo);
lastNodeOne.next = firstNodeOne;
lastNodeTwo.next = firstNodeTwo;
RunCupGame(nodeDictionaryOne, firstNodeOne, 9, 100);
RunCupGame(nodeDictionaryTwo, firstNodeTwo, 1000000, 10000000);
partOne = "";
LoopedListNode scanner = nodeDictionaryOne[1];
scanner = scanner.next;
while (scanner.value != 1)
{
partOne = partOne + scanner.value;
scanner = scanner.next;
}
scanner = nodeDictionaryTwo[1];
partTwo = ((long)scanner.next.value * (long)scanner.next.next.value).ToString();
}
public static void RangeToNodes(int start, int end, Dictionary <int, LoopedListNode> nodeDictionary, LoopedListNode last, out LoopedListNode tail)
{
for (int i = start; i <= end; i++)
{
LoopedListNode newNode = new LoopedListNode(i);
last.next = newNode;
last = newNode;
nodeDictionary[i] = newNode;
}
tail = last;
}
private static void StringToNodes(string input, Dictionary <int, LoopedListNode> nodeDictionary, out LoopedListNode first, out LoopedListNode last)
{
first = null;
last = null;
foreach (char c in input)
{
LoopedListNode newNode = new LoopedListNode(c - '0');
if (null == first)
{
first = newNode;
}
if (null != last)
{
last.next = newNode;
}
last = newNode;
nodeDictionary[c - '0'] = newNode;
}
}
