tron racers

using System;
using System.Linq;
using System.Text;

namespace BookWorm
{
    class Program
    {
        static void Main(string[] args)
        {
            int n = int.Parse(Console.ReadLine());

            string[,] matrix = new string[n, n];

            int firstRow = 0;
            int firstCol = 0;

            int secondRow = 0;
            int secondCol = 0;

            bool dead = false;


            for (int i = 0; i < n; i++)
            {
                string input = Console.ReadLine();

                for (int j = 0; j < n; j++)
                {
                    matrix[i, j] = input[j].ToString();

                    if (matrix[i, j] == "f")
                    {
                        firstRow = i;
                        firstCol = j;
                    }

                    else if (matrix[i, j] == "s")
                    {
                        secondRow = i;
                        secondCol = j;
                    }
                }
            }

            while (true)
            {
                string[] command = Console.ReadLine().Split().ToArray();

                if (command[0] == "up")
                {
                    firstRow--;

                    if (firstRow < 0)
                    {
                        firstRow = n - 1;
                    }
                }
                else if (command[0] == "down")
                {
                    firstRow++;

                    if (firstRow > n - 1)
                    {
                        firstRow = 0;
                    }
                }
                else if (command[0] == "left")
                {
                    firstCol--;

                    if (firstCol < 0)
                    {
                        firstCol = n - 1;
                    }
                }
                else if (command[0] == "right")
                {
                    firstCol++;

                    if (firstCol > n - 1)
                    {
                        firstCol = 0;
                    }
                }

                if (matrix[firstRow, firstCol] == "*")
                {
                    matrix[firstRow, firstCol] = "f";
                }
                else if(matrix[firstRow, firstCol] == "s")
                {
                    matrix[firstRow, firstCol] = "x";
                    dead = true;
                }

                if (dead)
                {
                    break;
                }

                if (command[1] == "up")
                {
                    secondRow--;

                    if (secondRow < 0)
                    {
                        secondRow = n - 1;
                    }
                }
                else if (command[1] == "down")
                {
                    secondRow++;

                    if (secondRow > n - 1)
                    {
                        secondRow = 0;
                    }
                }
                else if (command[1] == "left")
                {
                    secondCol--;

                    if (secondCol < 0)
                    {
                        secondCol = n - 1;
                    }
                }
                else if (command[1] == "right")
                {
                    secondCol++;

                    if (secondCol > n - 1)
                    {
                        secondCol = 0;
                    }
                }

                if (matrix[secondRow, secondCol] == "*")
                {
                    matrix[secondRow, secondCol] = "s";
                }
                else if(matrix[secondRow, secondCol] == "f")
                {
                    matrix[secondRow, secondCol] = "x";
                    dead = true;
                }

                if (dead)
                {
                    break;
                }
            }

            for (int i = 0; i < n; i++)
            {
                for (int j = 0; j < n; j++)
                {
                    Console.Write(matrix[i,j]);
                }

                Console.WriteLine();
            }


        }


    }

}