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=={{header|D}}==
D V.2, from the C version, writes a Portable Bit Map image to the stdout.
A more efficient version generates particles in a disk not too much larger than the current tree.
<lang d>import std.c.stdlib: rand, srand;
import std.c.time: time;
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static assert(WORLD_WIDTH * WORLD_HEIGHT > NUM_PARTICLES);
void dla(ref TWorld world) {
// put the tree seed
world[WORLD_HEIGHT / 2][WORLD_WIDTH / 2] = 1;
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foreach (_; 0 .. NUM_PARTICLES) {
// set particle's initial position
int px = rand() % WORLD_WIDTH;
int py = rand() % WORLD_HEIGHT;
while (true) { // move particle
// randomly choose a direction
int dx = rand() % 3 - 1; // offsets
int dy = rand() % 3 - 1;
if (dx + px < 0 || dx + px >= WORLD_WIDTH ||
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break;
} else {
// move particle
py += dy;
px += dx;
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toPBM(world);
}</lang>
One output, WORLD_WIDTH = 12, NUM_PARTICLES = 20:
<pre>P1
12 12
000000000000
000000000000
000000000000
000000010000
000000110000
000000111000
000011111000
000001100000
000001110000
000010100000
000001000000
000000000000</pre>
=={{header|Delphi}}==
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