考虑到for
循环中j
改变的时候,i
随着改变,可以直接从dfs(1)
跳到dfs(3)
class Solution {
public:
vector<vector<int>> res;
vector<int> path;
vector<vector<int>> subsets(vector<int>& nums) {
if (nums.empty()) return res;
dfs(nums, 0);
return res;
}
private:
void dfs(vector<int> &nums, int i)
{
res.push_back(path);
for(int j = i; j < nums.size(); j ++ )
{
path.push_back(nums[j]);
dfs(nums, j + 1);
path.pop_back();
}
}
};