问题描述
Given a set of distinct integers, nums, return all possible subsets.
Note: The solution set must not contain duplicate subsets.
For example, If nums = [1,2,3], a solution is:
[
[
3],
[
1],
[
2],
[
1,
2,
3],
[
1,
3],
[
2,
3],
[
1,
2],
[]
]
算法
深度优先，回溯算法
代码
public List<
List<Integer>> subsets(int[] nums) {
List<
List<Integer>> res =
new ArrayList<>();
dfs(res,
new ArrayList<>(), nums,
0);
return res;
}
public void dfs(
List<
List<Integer>> res,
List<Integer>
list, int[] nums, int start) {
res.add(
new ArrayList<>(
list));
for(int i=start;i<nums.length;i++) {
list.add(nums[i]);
dfs(res,
list, nums, i+
1);
list.remove(
list.size()-
1);
}
}
