Given a set of distinct integers, 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 = [1,2,3],
a solution is:
[ [3], [1], [2], [1,2,3], [1,3], [2,3], [1,2], [] ]
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public class Solution {
public
ArrayList<ArrayList<Integer>> subsets(int[] S) {
ArrayList<ArrayList<Integer> > result = new
ArrayList<ArrayList<Integer> >();
Arrays.sort(S);
int
num = (int)Math.pow(2, S.length);
for(int
i = 0; i < num; ++i){
ArrayList<Integer> list = new
ArrayList<Integer>();
String binaryreps = Integer.toBinaryString(i);
for(int
j = 0; j < binaryreps.length(); ++j){
if(binaryreps.charAt(binaryreps.length() - 1
- j) == ‘1‘)
list.add(S[j]);
}
result.add(list);
}
return
result;
}
} |