Subsets II

Given a collection of integers that might contain duplicates, S, return all possible subsets.

Note:

• Elements in a subset must be in non-descending order.
• The solution set must not contain duplicate subsets.

For example,
If S = [1,2,2], a solution is:

[  [2],  [1],  [1,2,2],  [2,2],  [1,2],  []]

class Solution:    # @param num, a list of integer    # @return a list of lists of integer    def subsetsWithDup(self, S):        if len(S)==0:            return [[]]                res = [[]]        S = sorted(S)                count = 1        for ind,elem in enumerate(S):            if ind==0:                start = 0;            elif S[ind-1] == S[ind]:                count = count + 1                start = len(res)*(count-1)/count            else:                start,count = 0,1                            newres = []            for index in range(start,len(res)):                elemres = res[index]                new = elemres[:]                new.append(elem)                newres.append(new)            res = res + newres                return res

not too hard