for (i = 0; i < 25; i++) {
unsigned x = i/5, y = i%5;
uint_fast32_t position;
position = board_position(x, y);
if (tiles[i] != TILE_EMPTY) {
for (i = 0; i < 25; i++) {
unsigned x = i/5, y = i%5;
uint_fast32_t position;
position = board_position(x, y);
if (tiles[i] != TILE_EMPTY) {