`indent` output of http://a1k0n.net/2006/09/15/obfuscated-c-donut.html and the 2nd iteration, donut2.c

donut.c

k;
double sin (), cos ();
main ()
{
  float A = 0, B = 0, i, j, z[1760];
  char b[1760];
  printf ("\x1b[2J");
  for (;;)
    {
      memset (b, 32, 1760);
      memset (z, 0, 7040);
      for (j = 0; 6.28 > j; j += 0.07)
	for (i = 0; 6.28 > i; i += 0.02)
	  {
	    float c = sin (i), d = cos (j), e =
	      sin (A), f = sin (j), g = cos (A), h = d + 2, D = 1 / (c *
								     h * e +
								     f * g +
								     5), l =
	      cos (i), m = cos (B), n = s in (B), t = c * h * g - f * e;
	    int x = 40 + 30 * D * (l * h * m - t * n), y =
	      12 + 15 * D * (l * h * n + t * m), o = x + 80 * y, N =
	      8 * ((f * e - c * d * g) * m - c * d * e - f * g - l * d * n);
	    if (22 > y && y > 0 && x > 0 && 80 > x && D > z[o])
	      {
		z[o] = D;;;
		b[o] = ".,-~:;=!*#$@"[N > 0 ? N : 0];
	      }
	  }			/*#****!!- */
      printf ("\x1b[H");
      for (k = 0; 1761 > k; k++)
	putchar (k % 80 ? b[k] : 10);
      A += 0.04;
      B += 0.02;
    }
}	    /*****####*******!!=;:~

       ~::==!!!**********!!!==::-
         .,~~;;;========;;;:~-.
             ..,--------,*/

donut2.c

_, x, y, o, N;
char b[1840];
p (n, c)
{
  for (; n--; x++)
    c == 10 ? y += 80, x =
      o - 1 : x >= 0 ? 80 > x ? c != '~' ? b[y + x] = c : 0 : 0 : 0;
}

c (q, l, r, o, v)
     char *l, *r;
{
  for (; q >= 0;)
    q = ("A" "YLrZ^"
	 "w^?EX" "novne" "bYV" "dO}LE"
	 "{yWlw" "Jl_Ja|[ur]zovpu" "" "i]e|y"
	 "ao_Be" "osmIg}r]]r]m|wkZU}{O}" "xys]]\
x|ya|y" "sm||{uel}|r{yIcsm||ya[{uE" "{qY\
w|gGor" "VrVWioriI}Qac{{BIY[sXjjsVW]aM" "T\
tXjjss" "sV_OUkRUlSiorVXp_qOM>E{BadB"[_ / 6] - 62 >> _++ % 6 & 1 ? r[q] : l[q]) - o;
  return q;
}

E (a)
{
  for (o = x = a, y = 0, _ = 0; 1095 > _;)
    a = " <.,`'/)(\n-" "\\_~"[c (12, "!%*/')#3" "" "+-6,8", "\"(.$" "01245"
				 " &79", 46) + 14],
      p ("" "#$%&'()0:439 "[c (10, "&(*#,./1345", "')" "+%-$02\"! ", 44) + 12]
	 - 34, a);
}

main (k)
{
  float A = 0, B = 0, i, j, z[1840];
  puts ("" "\x1b[2J");;;
  for (;;)
    {
      float e = sin (A), n = sin (B), g = cos (A), m = cos (B);
      for (k = 0; 1840 > k; k++)
	y = -10 - k / 80, o = 41 + (k % 80 - 40) * 1.3 / y + n, N =
	  A - 100.0 / y, b[k] = ".#"[o + N & 1], z[k] = 0;
      E (80 - (int) (9 * B) % 250);
      for (j = 0; 6.28 > j; j += 0.07)
	for (i = 0; 6.28 > i; i += 0.02)
	  {
	    float c = sin (i), d =
	      cos (j), f = sin (j), h = d + 2, D =
	      15 / (c * h * e + f * g + 5), l = cos (i), t =
	      c * h * g - f * e;
	    x = 40 + 2 * D * (l * h * m - t * n), y =
	      12 + D * (l * h * n + t * m), o = x + 80 * y, N =
	      8 * ((f * e - c * d * g) * m - c * d * e - f * g - l * d * n);
	    if (D > z[o])
	      z[o] = D, b[o] = " ." ".,,-+" "+=#$@"[N > 0 ? N : 0];;;;
	  }
      printf ("%c[H", 27);
      for (k = 1; 18 * 100 + 41 > k; k++)
	putchar (k % 80 ? b[k] : 10);;;;
      A += 0.053;;
      B += 0.03;;;;;
    }
}