public Day22Grid BuildNetwork(string[] instructions)
{
var result = new Day22Grid();
var network = instructions.Select(BuildNode).ToList();
result.Nodes = network;
var pairs = ViablePairs(null, result);
var adjacentPairs = pairs.Where(tuple =>
{
var first = tuple.Item1;
var second = tuple.Item2;
//If one dimension varies we have constrain the other.
return((first.X == second.X && (first.Y == second.Y + 1 || first.Y == second.Y - 1)) ||
(first.Y == second.Y && (first.X == second.X + 1 || first.X == second.X - 1)));
}).ToList();
result.AdjacentPairs = adjacentPairs;
return(result);
}
public List <Tuple <Day22Node, Day22Node> > ViablePairs(string[] input = null, Day22Grid network = null)
{
//Node A is not empty (its Used is not zero).
//Nodes A and B are not the same node.
//The data on node A(its Used) would fit on node B(its Avail).
//How many viable pairs of nodes are there?
if (input == null)
{
input = FileReader.ReadFile("day 22.txt").Skip(2).ToArray();
}
if (network == null)
{
network = BuildNetwork(input);
}
var pairs = new List <Tuple <Day22Node, Day22Node> >();
foreach (var a in network.Nodes)
{
foreach (var b in network.Nodes)
{
if (a == b)
{
continue;
}
if (a.Used == 0)
{
continue;
}
if (a.Used > b.Space)
{
continue;
}
pairs.Add(new Tuple <Day22Node, Day22Node>(a, b));
a.Connections++;
b.Connections++;
}
}
return(pairs);
}