LeetCode 491. Increasing Subsequences

public class Solution {    public List<List<Integer>> findSubsequences(int[] nums) {        Set<List<Integer>> list = new HashSet<List<Integer>>();        for (int i = 0; i < nums.length - 1; i++) {        	List<List<Integer>> tmp = new ArrayList<List<Integer>>();        	List<Integer> firstList = new ArrayList<Integer>();        	firstList.add(nums[i]);        	tmp.add(firstList);        	for (int j = i + 1; j < nums.length; j++) {        		List<List<Integer>> t = new ArrayList<List<Integer>>();        		for (List<Integer> tmpList : tmp) {        			List<Integer> ll = new ArrayList<Integer>();        			ll.addAll(tmpList);        			if (ll.get(ll.size() - 1) <= nums[j] && (nums[j] != nums[j - 1] || ll.contains(nums[j]))) {        				ll.add(nums[j]);            			t.add(ll);        			}        		}        		for (List<Integer> tmpList : t) tmp.add(tmpList);        	}        	if (tmp.size() > 1) {	        	tmp.remove(0);	        	for (List<Integer> tmpList : tmp) list.add(tmpList);        	}        }        return new ArrayList(list);    }}