a style question

[Dan Bernstein]

In article <1990Oct23.160116.10299 at athena.mit.edu> tada at athena.mit.edu (Michael J Zehr) writes:
>     v = (a[i-1][j-1] + a[i][j-1] + a[i-1][j+i] +
>          a[i-1][j] + a[i][j] + a[i-1][j+1] +
>          a[i-1][j+1] + a[i][j-1] + a[i-1][j+1])/9;

At a minimum I'd format this as

      v = (a[i-1][j-1] + a[i][j-1] + a[i-1][j+i] +
	   a[i-1][j  ] + a[i][j  ] + a[i-1][j+1] +
	   a[i-1][j+1] + a[i][j-1] + a[i-1][j+1])/9

which makes the j + i pretty obvious. Or a macro:

#define A(b,c) a[i+(b)][j+(c)]
      v = ( A(-1,-1) + A(0,-1) + A(-1,+i) +
	    A(-1, 0) + A(0, 0) + A(-1,+1) +
	    A(-1,+1) + A(0,-1) + A(-1,+1) ) / 9
#undef A

---Dan