Zerg! (BG Coder)

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

namespace ConsoleTests
{
    class ConsoleTests
    {
        static void Main()
        {
            Dictionary<string, decimal> dictionary =
                new Dictionary<string, decimal>();

            string[] phrases = new string[]
            {
                "Rawr","Rrrr","Hsst","Ssst","Grrr","Rarr","Mrrr","Psst","Uaah",
                "Uaha","Zzzz","Bauu","Djav","Myau","Gruh"
            };

            for (int i = 0; i < 15; i++)
            {
                dictionary.Add(phrases[i],i);
            }

            string input = Console.ReadLine();
            List<string> collection = new List<string>();

            int chunkSize = 4;
            int stringLength = input.Length;
            for (int i = 0; i < stringLength; i += chunkSize)
            {
                if (i + chunkSize > stringLength) chunkSize = stringLength - i;
                collection.Add(input.Substring(i, chunkSize));

            }

            collection.Reverse();

            List<decimal> results = new List<decimal>();

            for (decimal i = 0, j = 1; i < collection.Count; i++,j*=15)
            {
                string temp = collection[Convert.ToInt32(i)];
                if (dictionary.ContainsKey(temp))
                {
                    decimal tempDigit = dictionary[temp];
                    results.Add(tempDigit*j);
                }
            }

            Console.WriteLine(results.Sum());
        }
    }
}