Langton's ant: Difference between revisions

<lang aime>integer

is_white(list map, integer x, integer y)

{

integer p, w;

data b;

b = l_q_data(map, y);

w = b_character(b, x >> 3);

p = 1 << (7 - (x & 7));

b_replace(b, x >> 3, w ^ p);

return !(w & p);

}

void

ant(integer x, integer y, integer d, list map)

{

while (-1 < x && x < 100 && -1 < y && y < 100) {

if (is_white(map, x, y)) {

d += 3;

d &= 3;

} else {

d += 1;

d &= 3;

}

if (d & 1) {

y += (d & 2) - 1;

} else {

x += 1 - (d & 2);

}

}

}

integer

main(void)

{

integer i;

file f;

list l;

i = 100;

while (i) {

data b;

integer j;

i -= 1;

j = 13;

while (j) {

j -= 1;

b_append(b, 0);

}

l_l_data(l, -1, b);

}

ant(50, 50, 2, l);

f_open(f, "ant.pbm", OPEN_CREATE | OPEN_TRUNCATE | OPEN_WRITEONLY, 00644);

f_text(f, "P4\n100 100\n");

i = 100;

while (i) {

f_b_post(f, l_q_data(l, -i));

i -= 1;

}

return 0;

}</lang>