Adv2018/D3.2/Program.cs

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;

namespace D3._2
{
    class Program
    {
        static void Main(string[] args)
        {
            if (args.Length < 1) return;
            if (File.Exists(args[0]) == false) return;

            var file = File.OpenText(args[0]);

            var fabric = new HashSet<string>[1000, 1000];

            do
            {
                var line = file.ReadLine();
                if (line == null) break;

                var n = line.Split("@")[0];
                var l = line.Split("@")[1];

                var xy = l.Split(":")[0];
                var wh = l.Split(":")[1];

                var x = int.Parse(xy.Split(",")[0]);
                var y = int.Parse(xy.Split(",")[1]);
                var w = int.Parse(wh.Split("x")[0]);
                var h = int.Parse(wh.Split("x")[1]);

                for (int i = x; i < x + w; i++)
                {
                    for (int j = y; j < y + h; j++)
                    {
                        if (fabric[i, j] == null) fabric[i, j] = new HashSet<string>();
                        fabric[i, j].Add(n);
                    }
                }
            } while (true);

            Dictionary<string, bool> all = new Dictionary<string, bool>();
            for (int x = 0; x < 1000; x++)
            {
                for (int y = 0; y < 1000; y++)
                {
                    if (fabric[x, y] == null) continue;
                    var fl = fabric[x, y];

                    if (fl.Count == 1 && all.ContainsKey(fl.FirstOrDefault()) == false)
                    {
                        all.Add(fl.FirstOrDefault(), true);
                    }

                    if (fl.Count == 1) continue;

                    foreach (var f in fl)
                    {
                        if (all.ContainsKey(f) == false) all.Add(f, false);
                        else all[f] = false;
                    }
                }
            }

            Console.WriteLine(all.FirstOrDefault(a => a.Value == true));
        }
    }
}