using System;

using System.Linq;

using System.Text.RegularExpressions;

public class Program

    {

        const string Input = @"215

            193 124

            117 237 442

            218 935 347 235

            320 804 522 417 345

            229 601 723 835 133 124

            248 202 277 433 207 263 257

            359 464 504 528 516 716 871 182

            461 441 426 656 863 560 380 171 923

            381 348 573 533 447 632 387 176 975 449

            223 711 445 645 245 543 931 532 937 541 444

            330 131 333 928 377 733 017 778 839 168 197 197

            131 171 522 137 217 224 291 413 528 520 227 229 928

            223 626 034 683 839 053 627 310 713 999 629 817 410 121

            924 622 911 233 325 139 721 218 253 223 107 233 230 124 233";

        public static void Main()

        {

​

            string[] stringarray = ConvertStringToStringArray(Input);

            int[,] array = Build2DArray(stringarray);

            array = ReplacePrimeNumbersToZero(array);

​

            Console.WriteLine("{0}\n", maxPathSum(array));

​

​

​

        }

​

​

​

        private static string[] ConvertStringToStringArray(string s)

        {

            return s.Split('\n');

        }

        private static int[] ConvertStringArrayToIntegerArray(string row)

        {

            return Regex

                    .Matches(row, "[0-9]+")

                    .Cast<Match>()

                    .Select(m => int.Parse(m.Value)).ToArray();

        }

        private static int[,] Build2DArray(string[] splittedStringArray)

        {

​

            var twoDimensionalArray = new int[splittedStringArray.Length, splittedStringArray.Length + 1];

            var rowIndex = 0;

            foreach (var row in splittedStringArray)

            {

                var integerArray =ConvertStringArrayToIntegerArray(row);

                var columnIndex = 0;

                foreach (var integer in integerArray)

                {

                    twoDimensionalArray[rowIndex, columnIndex] = integer;

                    columnIndex++;

                }

                rowIndex++;

            }

            return twoDimensionalArray;

        }

​

        public static bool IsPrime(int i)

        {

            if (i == 0 || i == 1) return false;

            return Enumerable.Range(2, (int)Math.Sqrt(i) - 1).

                    All(divisor => i % divisor != 0);

        }

​

​

        private static int[,] ReplacePrimeNumbersToZero(int[,] array2D)

        {

            var length = array2D.GetLength(0);

            for (var i = 0; i < length; i++)

            {

                for (var j = 0; j < length; j++)

                {

                    if (array2D[i, j] == 0) continue;

​

                    if (IsPrime(array2D[i, j]))

                        array2D[i, j] = 0;

                }

            }

            return array2D;

        }

​

​

         private static int maxPathSum(int[,] array2D){

            int m= array2D.GetLength(0);

                for (int i = m - 2; i >= 0; i--)

                {

                    for (int j = 0; j <= i; j++)

                    {

                        if (array2D[i + 1, j] >

                               array2D[i + 1, j + 1])

                            array2D[i, j] +=

                                   array2D[i + 1, j];

                        else

                            array2D[i, j] +=

                               array2D[i + 1, j + 1];

                    }

                }

                return array2D[0, 0];

         }

    }