for(int i=0; i<4; i++) 
              { 
   
              for (int j = 4; j < i ; j--) 
              { 
                  Console.Write("x"); 
              } 
   
              for (int k = 1; k <= (i*2)+1; k++ ) 
              { 
                  Console.Write(" "); 
              } 
   
              for (int m = 4; m < i; m--) 
              { 
                  Console.Write("x"); 
              } 
                  Console.WriteLine(); 
              }