Adv2018/D8.2/Program.cs

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

namespace D8._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 text = file.ReadToEnd();
            var all = new List<string>(text.Split(" "));
            
            var root = getNode(all);

            Console.WriteLine($"Result is : {root.Value}");
        }

        static Node getNode(List<string> all)
        {
            var node = new Node();

            (int children, int metadatas) header = (int.Parse(all[0]), int.Parse(all[1]));

            all.RemoveAt(0);
            all.RemoveAt(0);

            for (int j = 0; j < header.children; j++)
            {
                var childnode = getNode(all);
                node.Children.Add(childnode);
            }

            int metasum = 0;

            for (int j = 0; j < header.metadatas; j++)
            {
                int meta = int.Parse(all[0]);
                all.RemoveAt(0);
                node.Meta.Add(meta);

                if (header.children == 0) metasum += meta;
                else
                {
                    var i = meta - 1;
                    if (i < 0 || i >= node.Children.Count) continue;

                    metasum += node.Children[i].Value;
                }
            }

            node.Value = metasum;

            return node;
        }
    }


    class Node
    {
        public List<int> Meta { get; set; }

        public List<Node> Children { get; set; }

        public int Value { get; set; }

        public Node()
        {
            Meta = new List<int>();
            Children = new List<Node>();
        }
    }
}