PROJECT EULER #18

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By starting at the top of the triangle below and moving to adjacent numbers on the row below, the maximum total from top to bottom is 23.

3
7 5
2 4 6
8 5 9 3

That is, 3 + 7 + 4 + 9 = 23.

Find the maximum total from top to bottom of the triangle below:

75
95 64
17 47 82
18 35 87 10
20 04 82 47 65
19 01 23 75 03 34
88 02 77 73 07 63 67
99 65 04 28 06 16 70 92
41 41 26 56 83 40 80 70 33
41 48 72 33 47 32 37 16 94 29
53 71 44 65 25 43 91 52 97 51 14
70 11 33 28 77 73 17 78 39 68 17 57
91 71 52 38 17 14 91 43 58 50 27 29 48
63 66 04 68 89 53 67 30 73 16 69 87 40 31
04 62 98 27 23 09 70 98 73 93 38 53 60 04 23

NOTE: As there are only 16384 routes, it is possible to solve this problem by trying every route. However, Problem 67, is the same challenge with a triangle containing one-hundred rows; it cannot be solved by brute force, and requires a clever method! ;o)

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

namespace ProjectEuler
{
   class Program
   {
       static void Main()
       {
           //Problem 18
           DateTime start = DateTime.Now;
           StreamReader sr = new StreamReader(@"../../littleTriangle.txt");
           //Treat the triangle as a 2 dimensional array[][]
           List<List<int>> triangle = new List<List<int>>();
           //make the triangle
           for (int i = 0; i < 15; i++)
           {
               string s = sr.ReadLine();
               char[] c = {' '};
               string[] sa = s.Split(c);
               List<int> line = new List<int>();
               foreach (string s1 in sa)
               {
                   line.Add(int.Parse(s1));
               }
               triangle.Add(line);
           }
           //row
           for (int i = 1; i < 15; i++)
           {
               //column
               for (int j = 0;j<=i; j++)
               {
                   //do the edges
                   if(j==0)
                       triangle[i][0] = triangle[i][0] + triangle[i - 1][0];
                   else if(j==triangle[i].Count-1)
                       triangle[i][triangle[i].Count-1] = triangle[i][triangle[i].Count - 1] + triangle[i - 1][triangle[i-1].Count-1];
                   //do the middle
                   else
                   {
                       triangle[i][j] = triangle[i - 1][j-1] + triangle[i][j] > triangle[i - 1][j ] + triangle[i][j]
                                       ? triangle[i - 1][j-1] + triangle[i][j]
                                       : triangle[i - 1][j ] + triangle[i][j];
                   }
               }
           }
           int max = 0;
           foreach (int i in triangle[triangle.Count-1])
           {
               max = i > max ? i : max;
           }
           Console.WriteLine(max);
           TimeSpan time = DateTime.Now-start;
           Console.WriteLine("This took {0}", time);
           Console.ReadKey();
       }
   }
}