FindingPath of list of string to print a word (ex: codingame)

 public class Program

{

      public static void Main()

      {

            List<string> listStr = new List<string>();

            listStr.Add("***a    ");

            listStr.Add("   e*    ");

            listStr.Add("    ***d**    ");

            listStr.Add("         e****    ");

            listStr.Add("             hgj***    ");

            

            string[,] grid = new string[35,35];

            

            for (int i = 0; i < listStr.Count; i++){

                  for(int j = 0; j < listStr[i].Length; j++){

                        grid[i,j] = listStr[i][j].ToString();

                        

                  }

            }

            

            Console.WriteLine(grid[0,0]);

            Console.WriteLine(grid[0,3]);

            Console.WriteLine(grid[1,3]);

            

            Dictionary<string, string> dict = new Dictionary<string, string>();

            

            for(int k = 0; k<35;k++){

                  for (int m = 0; m<35; m++){

                        //Console.WriteLine(grid[k,m]);

                        var sub_dict = SearchPath (k, m, grid);

                        foreach(var item in sub_dict){

                              if(!dict.ContainsKey(item.Key)){

                                    dict.Add(item.Key, item.Value);

                              }

                        }

                  }     

            }

            

            string strReturn = "";

            

            foreach(var dic in dict){

                  if(dic.Value != "*" && dic.Value != null){

                        //Console.Write(dic.Value);

                        strReturn = strReturn + dic.Value;

                  }

            }

            

            Console.WriteLine(strReturn.Replace(" ",""));

            

      }

      

      public static Dictionary<string,string> SearchPath (int x, int y, string[,] grid){

            Dictionary<string,string> toRetrun = new Dictionary<string,string>();

            if(grid[x,y] != null){

                  toRetrun.Add(String.Format("{0}{1}",(x).ToString(),y.ToString()), grid[x,y].ToString());

                  if(x - 1 >= 0 && x -1 < 35){

                        if(grid[x-1,y] != null && grid[x-1,y] != ""){

                              toRetrun.Add(String.Format("{0}{1}",(x-1).ToString(),y.ToString()), grid[x-1,y].ToString());

                        }

                  }

                  

                  if(x + 1 >= 0 && x+1 < 35){

                        if(grid[x+1,y] != null && grid[x+1,y] != ""){

                              toRetrun.Add(String.Format("{0}{1}",(x+1).ToString(),y.ToString()), grid[x+1,y].ToString());

                        }

                  }

                  

                  if(y - 1 >= 0 && y -1 < 35){

                        if(grid[x,y - 1] != null && grid[x,y - 1] !=""){

                              toRetrun.Add(String.Format("{0}{1}",x.ToString(),(y - 1).ToString()), grid[x,y - 1].ToString());

                        }

                  }

                  

                  if(y + 1 >= 0 && y+1 < 35){

                        if(grid[x,y + 1] != null && grid[x,y + 1] != ""){

                              toRetrun.Add(String.Format("{0}{1}",x.ToString(),(y+1).ToString()), grid[x,y+1].ToString());

                        }

                  }

                  

                  

            }

            

            

            return toRetrun;

      }

}