Fix some latent bugs left over

main.c

@@ -16,6 +16,7 @@
 #include <raylib.h>
 #include <raymath.h>
 
+#define STB_IMAGE_WRITE_IMPLEMENTATION
 #include <stb/stb_image_write.h>
 
 #define WIDTH       1024
@@ -162,7 +163,7 @@ int main(void)
     else if (IsKeyPressed(KEY_SPACE))
     {
       threads_cancel_render();
-      memset(cells, 0, WIDTH * HEIGHT);
+      memset(cells, 0, sizeof(cells[0]) * WIDTH * HEIGHT);
       MAX_ITER *= 2;
       rendered = false;
       threads_start_render(args);