Adv2016/D01.2/Program.cs

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

namespace D01._2
{
    class Program
    {
        static void Main(string[] args)
        {
            if (args.Length < 1) throw new ArgumentException();
            if (File.Exists(args[0]) == false) throw new FileNotFoundException();

            string input = File.ReadAllText(args[0]);

            var visited = new HashSet<(int, int)>()
            {
                (0, 0)
            };

            (int x, int y, int r) coord = (0, 0, 0);
            foreach (var i in input.Split(", "))
            {
                int n = int.Parse(i.Substring(1));
                switch (i[0])
                {
                    case 'R': coord.r += 90; break;
                    case 'L': coord.r -= 90; break;
                }

                if (coord.r < 0) coord.r += 360;
                if (coord.r >= 360) coord.r -= 360;

                if (Visit(ref coord, n, visited) == false)
                    break;
            }

            var manhattan = Math.Abs(coord.x) + Math.Abs(coord.y);
            Console.WriteLine($"Distance is : {manhattan}");
        }

        private static bool Visit(ref (int x, int y, int r) coord, int n, HashSet<(int, int)> visited)
        {
            for (var i = 0; i < n; ++i)
            {
                switch (coord.r)
                {
                    case 0: coord.y --; break;
                    case 90: coord.x ++; break;
                    case 180: coord.y ++; break;
                    case 270: coord.x --; break;
                }

                if (visited.Add((coord.x, coord.y)) == false)
                    return false;
            }

            return true;
        }

        private static void HashSet(int v1, object x, int v2, object y, int v3, object r)
        {
            throw new NotImplementedException();
        }
    }
}