public boolean sUp() {
		boolean change = false;
		for (int i = 0; i < 4; i++) {
			for (int j = 0; j < 4; j++) {
				boolean tmp = mUp(i, j);
				if (tmp)
					change = true;
			}
			if (aUp(i)){
				change = true;
			}
		}

		if (change) {
			genTile();
		}
		return change;
	}