text: 
  for (t=0; t<=T-1; t++)  
    for (i=1; i<=N-2; i++)  
      for (j=1; j<=N-2; j++)  
        A[i][j] = (A[i-1][j-1] + A[i-1][j] + A[i-1][j+1]
  		 + A[i][j-1] + A[i][j] + A[i][j+1]
  		 + A[i+1][j-1] + A[i+1][j] + A[i+1][j+1])/9.0;
  