Longest Increasing Subsequence
	
	/**
	 * Find the longest subsequence of a given sequence
	 * 
	 * e.g.
	 * 		{9, 6, 2, 4, 5, 1, 3, 3, 7, 8}
	 * 
	 * LIS: {4, 5, 7, 8}
	 * 
	 * */