private void clearGraph(States state) {
		for (int i = 0; i < N; i++) {
			if (state == States.ARR_ADJ)
				Arrays.fill(arr_adj[i], 0);
			if (state == States.ARR_INC)
				Arrays.fill(arr_inc[i], 0);
			if (state == States.LIST_ADJ)
				list_adj[i] = new ArrayList<ListNode>();
		}
	}